Oklahoma Climatological Survey http://climate.ok.gov Oklahoma Climatological Survey en-us stdrovia@mesonet.org (Stdrovia Blackburn) stdrovia@mesonet.org (Stdrovia Blackburn) Copyright 2003-2005 Board of Regents of the University of Oklahoma Drought Drowning In Oklahoma http://climate.ok.gov/ Heavy rains produced by dying tropical systems from both the Atlantic and Pacific oceans have nearly eradicated any trace of drought in Oklahoma over the last seven days. Remnants of Tropical Storm Lowell crossed western Oklahoma and merged with a cold front to inundate that part of the state while the remnants of Hurricane Ike struck eastern Oklahoma. The U.S. Drought Monitor now portrays the western two-thirds of the Panhandle as the lone section of the state currently experiencing excessive dryness. The rains, which largely fell between September 10 and September 14, totaled between 4-7 inches in the northwestern half of the state and 1-4 inches in the southeastern half, according to data from the Oklahoma Mesonet. Fairview recorded the most rainfall with 11.83 inches. That breaks the old record of 11.28 inches for September total rainfall in Fairview, set in 1936. Records for Fairview end in 1977, however, and begin in 1932.

The state is coming off of the 23rd wettest summer (12.53 inches of rainfall averaged statewide, 2.76 above normal) on record, and the 18th wettest August (4.38 inches statewide average, 1.61 inches above normal). For the year thus far, from January 1-September 17, the statewide average rainfall total of 32.31 inches ranks as the 9th wettest such period on record, more than 5 inches above normal. Northeastern Oklahoma is experiencing its wettest year-to-date on record with 48.39 inches, on average, nearly 18 inches above normal.

The Oklahoma panhandle continues to have drought conditions deemed "moderate" and "severe", a far cry from "exceptional" - the Drought Monitor's worst designation - label they had for most of the summer. For the year thus far, as of September 17, the Panhandle still has a deficit of nearly 4 inches to rank as the 21st driest such period on record.

]]> September 19, 2008 Excessive Rainfall from Hurricanes http://climate.ok.gov/ We are all aware of the risks of hurricanes when they come ashore – high winds, storm surges, and occasional tornadoes. But sometimes hurricanes are at their most destructive well away from the coast, where you rarely see live media coverage. Inland flooding associated with the remnants of tropical systems have caused some of the most extreme flooding in Oklahoma’s history. Such is the concern in Oklahoma during the next few days as the remnants of Pacific Hurricane Lowell and Atlantic Hurricane Ike are forecast to move into the Southern Plains region. Widespread flooding rainfall over much of Oklahoma is a possibility with these systems, according to the National Weather Service.

There have been some phenomenal one-day totals associated with the remnants of tropical systems in Oklahoma, such as the 15.68 inches that fell in Enid on October 11, 1973 from an isolated thunderstorm, but it has been the continuous rains over several days that have racked up the greatest totals.

More than 14 inches of rain over a 3-day period is needed just to make the Top-10 list of 3-day rainfall totals, according to archives from the Oklahoma Climatological Survey. The greatest 3-day total occurred between October 12th and 14th, 1981, when several locations reported more than 18 inches of rain in Marshall and Johnston counties.

So were these excessive totals caused by tropical storms? The answer is yes, but not the ones that may come to our minds. Although Atlantic hurricanes grab our attention, it is the remnants of Pacific Hurricanes that have wrecked the most havoc on our state. The October 1981 event was caused by Hurricane Norma, which went on to drop nearly 25 inches of rainfall in one week! Hurricane Paine came in second on the list. Of these Top-10 events, none were associated with tropical systems from the Atlantic Ocean.

You can learn more about how Pacific hurricanes have affected Oklahoma's weather in the Fall 2006 edition of Oklahoma Climate, http://climate.mesonet.org/seasonal_summary.html.

]]> September 10, 2008 August 2008 Climate Summary http://climate.ok.gov/ August was a wet month for most of the state as record-setting precipitation fell over parts of central and southern Oklahoma. Oklahoma City in particular set several precipitation records, including their All-time August rainfall total and all-time August daily rainfall total. Statewide, the wet weather propelled the month to the 18th wettest August on record. The rain and associated cloud cover helped the month finish as the 27th coolest August on record as well. The only area not enjoying the abundant moisture was north central Oklahoma which suffered its 25th driest August on record. Oklahoma City's official total of nearly 10 inches for the month breaks the old record for August rainfall set in 1906. Severe weather was sporadically reported. Large hail and high winds did occur, but flooding was the most frequent severe weather type. The year's high temperature of 110 degrees was reported at Freedom on the fourth. The highest rainfall total was recorded at Waurika, which came in with nearly 12 inches.

Full monthly summary available online at:
http://climate.mesonet.org/monthly_summary.html

]]> September 5, 2008 Drought-Busting Rains Fall http://climate.ok.gov/ Prodigious rainfall amounts across Oklahoma have helped propel August to a top-three finish for precipitation. Even the Panhandle, which had been mired in severe drought conditions, helped push the total higher with their third-wettest August on record thus far. In fact, every region of the state has been decidedly on the wet side of normal for the month save for north central Oklahoma which has experienced a deficit of about an inch. The southwest and southeast corners of the state have each experienced their second-wettest August on record with surpluses of more than three inches.

The rains started in earnest on August 7 and have continued nearly uninterrupted through August 20. Some of the heavier amounts recorded by the Oklahoma Mesonet during this time include a 5.58-inch total from Shawnee on the 11th and totals of over six inches from Walters and Waurika on the 18th. The Oklahoma Mesonet site at Waurika recorded the most precipitation for the month with 11.7 inches. Blackwell recorded a paltry 0.5 inches over that same period.

]]> August 20, 2008 July 2008 Climate Summary http://climate.ok.gov/ July was fairly normal for these parts, both statistically and weather-wise. The month ended as the 53rd warmest and 47th driest out of the 114 years on record. The northern half of the state saw the most rain and accounted for the bulk of the near-normal total while the southeast went thirsty. Severe weather was thankfully sparse after a few months of tumultuous weather. Drought conditions lessened somewhat in the Oklahoma Panhandle with 2-4 inches of much-needed rainfall. Cimarron County, however, continued with conditions compared to the Dust Bowl days, according to long-time residents of the area.

Full monthly summary available online at:
http://climate.mesonet.org/monthly_summary.html

]]> August 7, 2008 Heat Wave Cooks Oklahoma http://climate.ok.gov/ Monday's excessive heat brought the statewide-averaged high temperature to 103.42, based on 120 Oklahoma Mesonet stations across the state. This value represented the warmest afternoon observed in Oklahoma since August 2006, and the 23rd-warmest day in the history of the Mesonet (14+ years since 1994). The Mesonet observation of 110 at Freedom was the highest temperature observed by the Mesonet since August 2003.

]]> August 4, 2008 Teachers Attend 16th EarthStorm Weather Workshop sponsored by the Oklahoma Climatological Survey and the Oklahoma Mesonet http://climate.ok.gov/ The Oklahoma Climatological Survey and the Oklahoma Mesonet will welcome 42 K-12 teachers to the EarthStorm Weather Workshop in Norman, OK on July 15-18, 2008. The EarthStorm Workshop will be held at the National Weather Center (NWC). Teachers will enjoy four days touring weather facilities and presentations from scientists and University of Oklahoma students. New teachers will begin learning basic meteorology concepts and use Oklahoma Mesonet data in classroom activities. Veteran EarthStorm teachers will join the us the second day.

Days 2-4 will cover thunderstorms from all sides. Speakers will explain weather ingredients that lead to severe events, explain storm structure and development and show video from actual storms. A case study will look back at the Greensburg, KS EF-5 tornado from 2007. Staff from the Norman National Weather Service Forecast Office will answer questions during an evening balloon launch. Afterwards, the teachers will view the Oklahoma Mesonet tower located in the parking lot (This tower is used for tour groups and is not part of the official data records of the Oklahoma Mesonet.).

Teachers will have the opportunity to learn about current and future radar technologies. They will visit the Phased Array Radar on north campus and get up close with a SMART-R radar (the ones mounted on the back of a truck). We will end our discussions on severe weather by looking back at the Union City Tornado of 1973 and Tropical Storm Erin from 2007.

Staff from the National Weather Center partner agencies and University of Oklahoma students will form two panels to discuss their high school, college and/or work experiences. The teachers will be able to ask questions about the skills need to earn a degree and how they can better help prepare their students for college.

We hope the teachers leave with an eagerness to share what they learned with their students and colleagues.

]]> July 14, 2008 June 2008 Climate Summary http://climate.ok.gov/ June was a very active weather month in Oklahoma with a large number of severe storm reports. Heavy rains in all but the extreme northwest and south meant a wet month as well – the 25th wettest June on record, in fact. The Oklahoma Panhandle continued without significant precipitation, still mired in severe drought conditions. The month also finished as the 32nd warmest June on record. There were 34 reported instances of hail at least two inches or greater during the month to go along with 23 instances of winds greater than 70 mph. Not to be outdone, there were 25 reports of flooding, most of which occurred in northeastern Oklahoma.

Full monthly summary available online at:
http://climate.mesonet.org/monthly_summary.html

]]> July 10, 2008 May 2008 Climate Summary http://climate.ok.gov/ A major return of significant tornadoes occurred in May. Seven twisters rated at least EF-2 in intensity touched down within the state's confines in addition to 24 of the weak variety. The most unfortunate statistic was the cost in lives, however, as a violent EF-4 tornado plowed through the small town of Picher on May 10th and claimed the souls of six Oklahomans. Another tornado struck and destroyed a hog farming operation near Lacey with the entire episode shown live from a local news helicopter. The preliminary count of 31 tornadoes was the most for any month since May 2003 when 59 tornadoes touched down. The six deaths were the most in a single day since the deadly May 3, 1999, Moore-South Oklahoma City EF-5 that killed 36. Severe weather was widespread throughout the month, especially in the form of large hail. Twenty-four instances of hail two inches or greater were reported to go along with the tornadoes. Oddly, despite all the tornadoes and severe weather the month's final rainfall tally finished below normal for much of the state. The statewide average rainfall was a tad below normal to rank as the 53rd driest since 1895. The month was fairly warm as well and ranked as the 49th warmest on record. The spring season ranked as the 20th wettest on record but a tad cool with the 51st-coolest ranking.

Full monthly summary available online at:
http://climate.mesonet.org/monthly_summary.html

]]> June 10, 2008 Oklahoma's State of the Climate: May 20-28 http://climate.ok.gov/ Drought, flooding rains and severe weather were the big story during the past week - certainly not atypical May weather in Oklahoma. The tornadoes grab the headlines, of course, but another less-telegenic disaster continued to worsen in the Panhandle as the National Drought Mitigation Center upgraded the drought in that region from "severe" to "extreme." The drought conditions were worse in the western half of the Panhandle where precipitation totals since the beginning of the current water year - October 1, 2007 - dropped to less than 20 percent of normal.

The severe weather was highlighted by a series of tornadoes that struck northwest Oklahoma, the first in Harper County on the 23rd which damaged homes and outbuildings northeast of Fort Supply. Preliminary reports placed the tornado in the "significant" category, rated at least an EF-2 on the Enhanced Fujita Scale of tornado intensity. At least eight tornadoes touched down on the 24th in Kingfisher, Garfield and Noble Counties, but that count could increase after a closer look at damaged areas. That series of tornadoes was broadcast nationwide as local television reports were picked up by several cable news channels. One of the tornadoes wowed television audiences as it destroyed a hog farm near Lacey.

Large hail was another unwanted and frequent visitor during the period, from baseball size hail on the 22nd near Kingfisher to softball size hail in Roger Mills County on the 26th. The hail damaged wheat crops nearly ready for harvesting in northwestern, north central, and southwestern Oklahoma, and stripped the bark off of trees in Jackson County.

Precipitation associated with the thunderstorms was heavy in many areas, especially in north central Oklahoma where the Mesonet station at Red Rock recorded 5.6 inches of rainfall for the period. Four-to-five inch amounts were common across that area. Temperatures continued unseasonably warm across the state and combined with moisture from the Gulf of Mexico to make for uncomfortable afternoons. The state's highest temperature occurred at Altus on three separate days: the 23rd, 24th and 26th. In contrast, Hooker’s high temperature reached a relatively chilly 67 degrees on the 27th. The state's lowest temperature of 44 degrees was recorded by the Mesonet site at Boise City on the 24th. On that same day, the minimum temperature at Clayton was 78 degrees.

]]> May 29, 2008 April 2008 Monthly Climate Summary Online Now http://climate.ok.gov/ The April 2008 Monthly Climate Summary is now online at: http://climate.mesonet.org/monthly_summary.html

Highlights:

  • Same as it ever was...drought in the west and flooding in the east
  • First significant tornadoes in the state since May 2007
  • Microburst winds wreak havoc in Muldrow
  • The 32nd coolest April since 1895

]]> May 9, 2008 Oklahoma Climatological Survey http://climate.ok.gov Oklahoma Climatological Survey en-us stdrovia@mesonet.org (Stdrovia Blackburn) stdrovia@mesonet.org (Stdrovia Blackburn) Copyright 2003-2005 Board of Regents of the University of Oklahoma What Do You Mean Drought? http://climate.ok.gov/ In the midst of another wet spring, why would the Oklahoma Climatological Survey post a story about drought? That's because portions of the Oklahoma Panhandle are in an extended dry period. This week, the Drought Monitor (http://www.drought.gov/) moved portions of Cimarron and Texas Counties up to D2 - Severe Drought.

While the year-to-date total for the state stands as the 13th wettest on record, the Panhandle and far northwestern Oklahoma have recorded their 11th driest January-April period on record. Boise City has recorded less than one inch of precipitation in the last 6 months. In fact, the meager total of 0.81 inch from November 2007 - April 2008 is their lowest accumulation on record by a wide margin. It has been 220 days since the Mesonet station at Boise City recorded one-quarter inch of precipitation from a single storm. The last time the area recorded significant precipitation was during the December 2006 blizzard

Worse news yet is that forecasters expect the drought to continue through the summer. As the region moves towards its rainy season, it will be important to keep a close eye on the weather and the impacts. We encourage you to tell us about how the drought is impacting you. Send a report in to the Drought Impact Reporter (also on the Drought Portal website, www.drought.gov), or e-mail us at ocs@ou.edu.

]]> May 2, 2008 University of Oklahoma Takes Part in Upcoming Feasibility Study http://climate.ok.gov/ NORMAN--Through an international, competitive bidding process, the University of Oklahoma was recently selected by the Meteorological and Hydrological Service (DHMZ-Drzavni hidrometeoroloski zavod) of the Republic of Croatia to undertake a comprehensive modernization Feasibility Study for the DHMZ. Led by Regents Professor Ken Crawford, Director of the Oklahoma Climatological Survey, the study team consists of a diverse collection of meteorological experts from the National Weather Center. The team will evaluate the current monitoring equipment in place throughout Croatia and the forecasting techniques currently in use, and develop a plan to modernize all aspects of the country's monitoring, analysis, forecasting, and warning systems.

Adverse weather, flooding activity, and environmental hazards cost the Croatian economy approximately $218M annually, severely impacting the quality of life of its citizens and reducing economic development. The upcoming Feasibility Study will provide critical justification and evidence required to proceed forward with obtaining the necessary funding to implement a national upgrade and modernization of the DHMZ services. The project will include a series of in-country visits to all parts of Croatia and is expected to require approximately one year to complete. This feasibility study will be performed utilizing and harmonizing the outcomes of the Feasibility Study on the Strengthening of the Hydrometeorological Services in the South Eastern Europe completed by the Finish Meteorological Institute, Finish governmental organization VTT and the DHMZ under the umbrella of the World Meteorological Organization, World Bank and UNISDR.

"The selection of the University of Oklahoma to carry out this feasibility study is further evidence of the high international regard for the several University weather and climate programs involved," said John Snow, Dean of the College of Atmospheric and Geographic Sciences. Snow also noted that "we are excited about the possibilities this selection opens up for our programs to do similar studies throughout southeastern Europe."

This study has been organized through the recently established Office of Weather Programs and Projects at OU. A part of the Weather Sphere -- a collaborative partnership centered in Norman, Oklahoma, growing to become international leaders in weather and climate-related education and training, research and development, and operations and services -- OWPP specializes in the transfer of meteorological knowledge to applied meteorological projects both nationally and internationally.

]]> April 17, 2008 March 2008 Climate Summary http://climate.ok.gov/ Remarkable rainfall totals from the eastern half of the state propelled March to the sixth wettest since 1895. The southeastern corner averaged more than 12 inches of rain for the month to eclipse the established normal by more than eight inches, ranking as the wettest March on record for that part of the state. Rainfall tapered off towards the Panhandle, leaving that region in a cloud of dust where less than a quarter of an inch of rain fell on average. As for temperature, the month ended in the middle of the pack and ranked as the 43rd warmest on record. Three major storm systems provided most of the rain and a fair amount of severe weather as well. Officially, four tornadoes touched down during the month in addition to four others that were not yet confirmed. The worst of the tornadoes was an EF1 that struck Edmond and did significant residential property damage. Buffalo received hail the size of softballs early in the month, and extensive flooding occurred in eastern Oklahoma with each storm system. A significant snowstorm struck southeastern Oklahoma early in the month, dropping more than a foot of snow in LeFlore County. An even earlier snowstorm dropped nearly a half of a foot in the same general area.

Full monthly summary available online at: http://climate.mesonet.org/monthly_summary.html

]]> April 4, 2008 Winter 2007-2008 Summary http://climate.ok.gov/ The Oklahoma Climatological Survey is proud to announce the Winter 2007-2008 edition of its seasonal climate series "Oklahoma Climate," available online at: http://climate.mesonet.org/seasonal_summary.html.

Enjoy some stuffing with the following great stories:

  • Is the December 2007 ice storm the worst in state history? We compare past events and let you decide.
  • NEXRAD is the best radar system ever! Well, until now...learn about the new polarimetric radar in this issue.
  • A new feature! Learn about luminaries of the Norman weather scene with our interview section.
  • Climate change looms on the horizon. The Climate Survey weighs in on the issue with our official statement on climate change.
  • Our friends at the National Weather Service look at last summer's brush with Tropical Storm Erin once again,this time focusing on the flooding.
  • Our classroom exercise helps students understand ice storms and the damage they can inflict.
  • Spring horticulture tips for lawn and garden enthusiasts.
  • An agricultural summary of the fall months.
  • A fall climate summary, including daily highlights.
  • Winter weather myths are just as dangerous as severe weather myths. Stay safe by reading our own version of "Mythbusters"!
]]> February 28, 2008 <![CDATA[Beneficial Rains Fall]]> http://climate.ok.gov/ Beneficial rains fell over most of Oklahoma February 15-17 which helped to alleviate recent wildfire flare-ups. The moisture also delayed the progress of drought conditions which had once again begun to advance across the western and southern portions of our state. The moisture was even more welcome since it came mostly in the form of a very cold rain, as opposed to the freezing rain that was feared across the western half of the state. A few problems with electric power utilities developed late Friday night and into early Saturday morning, but warm air moved into the region from the south which helped melt accumulated ice from power lines and trees before the calamity of the December 2007 ice storm was relived.

Most of the state saw more than an inch of liquid precipitation with 94 of 118 Oklahoma Mesonet sites hitting that mark. The precipitation was more plentiful in west central, central, and southeastern Oklahoma, however, where amounts ranged from 2-3 inches in general. The Oklahoma Mesonet site at Talihina led the state with 3.40 inches.

Unfortunately, the western portions of the Oklahoma Panhandle remains parched. Drought conditions have continued to worsen in that area, which never saw the rains that most of the state enjoyed during the previous year.

The top-ten storm-total precipitation amounts
from the Oklahoma Mesonet - February 15-17, 2008
Mesonet Site Storm-Total Rainfall (inches)

Talihina

3.40

Clayton

3.27

Antlers

3.11

Oklahoma City North

2.79

Wister

2.60

Minco

2.58

Hugo

2.56

Weatherford

2.49

Bessie

2.41

El Reno

2.34

]]> February 18, 2008 <![CDATA[Our Long and Hard Winter?]]> http://climate.ok.gov/ The 2007-08 winter thus far has seemed like a doozy. Maybe it was the gargantuan ice storm in December or the frigid temperatures we've seemingly been stuck in since Thanksgiving. When it comes to the weather, however, our memories are sometimes worse than reality. So, let's take a look at the statistics for this winter and see where we stack up on the miserably long-hard winter scale.

Since the beginning of the climatological winter on December 1, our statewide average temperature has actually been a bit warmer than normal by a few tenths of a degree. At least it's been wetter than normal, right? Sure, as long as you live in the Panhandle, which is experiencing its 15th wettest December 1-January 24 period on record. How about drier than normal then? Yep, but once again, as long as you live somewhere in the southern one-half of the state, or along the extreme western border. Southeastern Oklahoma, for instance, is having its 23rd driest winter on record thus far at more than an inch and a half below normal. Of course, some places in the dry area have been wet, and some places in the wet areas have been dry. That doesn't seem to make sense, but as most Oklahomans can attest, weather rarely does. All-in-all, the statewide average precipitation total for the winter is 2.65 inches - about a half of an inch below normal.

Our long-range forecasts are all pointing to drier and warmer weather for the next couple of months due to La Nina conditions in the equatorial pacific waters. So about all we can do is sit back and see what happens during the rest of this long-hard, strike that, fairly normal winter (save for a gargantuan ice storm, of course). And someday, today's kids can tell their children how they had to walk to school 10 miles in fairly normal weather.

December 1-January 24 Statewide Weather Statistics

Average High Temperature (F)

49.3

Average Low Temperature (F)

25.8

Average Temperature (F)

37.6

Average Rainfall

2.65

]]> January 25, 2008 <![CDATA[2007: Year in Review]]> http://climate.ok.gov/ As we pass from 2007 to 2008 and the sound of chain saws and wood chippers diminish across Oklahoma, it provides an opportune time to reflect on the previous 365 days. The key to your 2007 weather experience in Oklahoma was undoubtedly WHERE you were during 2007 in Oklahoma. If you were in the Panhandle, the year was probably spent fighting pangs of jealousy towards central Oklahoma's abundant precipitation. If you were in central Oklahoma, you probably looked with envy at the dry weather of the Panhandle. And somewhere in between the droughts and floods, the truth is most Oklahomans enjoyed a very wet and somewhat warm year.

For the record, the statewide average precipitation total of 41.04 inches is about four inches above normal, making 2007 the 14th wettest year since records began in 1895. According to the Oklahoma Mesonet, rainfall totals across the state ranged from a high of 59.4 inches at the Red Rock in Noble County to a measly 12.0 inches at Goodwell in Texas County. Rankings-wise, the Panhandle experienced its 21st driest year on record while central Oklahoma enjoyed its wettest year on record (between floods, that is).

The year was warmer than normal, but not exceedingly so, ranking statewide as the 39th warmest since 1895, or about 0.3 degrees above normal. The Panhandle was the only region to finish below normal, yet it was still in the middle of the pack, ranked as the 52nd warmest on record.

2007 Oklahoma Mesonet Precipitation Statistics
Climate
Division		 Precip.
(inches)		 Departure
from Normal		 Rank since
1895		 Wettest
on Record		 Driest
on Record		 2006
Panhandle 15.12" -5.98" 15th driest 33.25 (1941) 9.50 (1910) 18.16
N. Central 37.67" 6.02" 10th wettest 45.52 (1957) 14.50 (1956) 19.84
Northeast 46.11" 4.14" 26th wettest 60.49 (1941) 21.84 (1963) 31.76
W. Central 36.69" 7.60" 7th wettest 43.04 (1997) 10.30 (1910) 23.31
Central 52.51" 14.52" 1st wettest 50.56 (1908) 16.10 (1910) 27.49
E. Central 46.25" 0.16" 41st wettest 67.06 (1973) 23.15 (1963) 39.00
Southwest 37.12" 6.32" 13th wettest 44.05 (1941) 11.96 (1910) 23.67
S. Central 42.53" 1.57" 27th wettest 57.51 (1957) 19.63 (1963) 30.93
Southeast 50.30" -0.64" 47th wettest 71.98 (1990) 27.48 (1963) 46.98
Statewide 40.77" 4.08" 14th wettest 48.23 (1957) 19.04 (1910) 28.69

2007 Oklahoma Mesonet Temperature Statistics
Climate
Division		 Avg.
Temp		 Departure
from Normal		 Rank since
1895		 Hottest
on Record		 Coldest
on Record		 2006
Panhandle 56.1°F -0.3°F 52nd warmest 59.5 (1954) 53.3 (1912) 58.4
N. Central 58.7°F 0.2°F 48th warmest 62.2 (1954) 56.1 (1912) 61.1
Northeast 59.7°F 0.8°F 30th warmest 62.4 (1954) 56.2 (1917) 61.3
W. Central 59.2°F 0.4°F 44th warmest 62.4 (1954) 56.6 (1979) 61.9
Central 60.3°F 0.3°F 37th warmest 63.1 (1954) 57.3 (1912) 62.8
E. Central 60.9°F 0.6°F 34th warmest 63.4 (1954) 58.1 (1917) 62.8
Southwest 61.0°F 0.0°F 55th warmest 64.1 (1954) 58.8 (1906) 63.5
S. Central 62.0°F 0.1°F 50th warmest 64.7 (2006) 59.8 (1912) 64.7
Southeast 62.0°F 0.9°F 36th warmest 64.5 (1921) 58.9 (1979) 63.3
Statewide 59.9°F 0.3°F 39th warmest 62.8 (1954) 57.3 (1912) 62.2

]]> January 3, 2008 ICE STORM 2007 http://climate.ok.gov/ The ice storm of December 8-10, 2007, is yet another in a list of significant icing events to hit the state since the turn of the millennium, and the second this year.  With estimates as high as 630,000 customers without power, it dwarfs the previous high of approximately 255,000 during the January 2002 ice storm. That fact begs the question:  "Was this ice storm more powerful than those of the previous decade?" That answer is difficult to ascertain. According to the sheer numbers of those left powerless, the answer would obviously be a resounding "yes".  As far as the amount of precipitation and ice accumulation goes, the amounts seem to be similar. So why is there such a discrepancy in the number of power outages? Location, location, location.

Keep in mind that the state's major metropolitan areas of Oklahoma City and Tulsa have largely received only glancing blows from the previous icing events. In fact, the I-44 corridor has seemed to act as a dividing line between the worst effects during past events. The December 2000 storm mainly affected areas south and east of I-44, while the January 2002 event devastated areas to the north and west of that interstate highway. It has always been well understood that should Oklahoma City or Tulsa receive the amount of ice as in the southeast or northwest during these previous events, the amount of structural and property damage would increase dramatically.

As for damage estimates, the tallies from previous storms soared into the hundreds of millions. Damage from the current storm will undoubtedly soar into that territory as well as clean-up begins and the impacts become more well-defined. The true cost of weather in Oklahoma is measured in lives, however, and the current storm has been particularly deadly. Twelve fatalities have been attributed to the inclement weather, all due to motor vehicle accidents.

Oklahoma Ice Storms Since 2000

  • December 25-27, 2000: Major snow and ice storms struck statewide, especially powerful in southeast quarter. Power was lost to at least 120,000 homes and businesses, including 90 percent of the residents of McIntosh, Latimer, and Pittsburg counties. Extended power outages also led to disruptions of local water supplies in several areas. At least 27 fatalities were attributable to the extreme weather conditions, which extended well into January 2001. Total property damage in the state was approximately $170 million.
  • January 28-30, 2002:  This powerful winter storm wreaked havoc on the northwestern half of the state, and none suffered more than the state's power suppliers.  The storm left over $100 million of damage in its wake, leaving some 255,000 residences and businesses without power.  A week after the icy system exited the state, 39,000 Oklahoma residents were still in the dark as utility companies worked around the clock to replace snapped poles and downed power lines.  Enid, a city of 47,000, was entirely without electricity for days.  Power companies estimated that power could be lost for up to two months in some rural areas of northwestern Oklahoma. Southwestern Oklahoma State University in Weatherford closed its doors for only the 4th time in its 100-year history.  The Oklahoma Association of Electric Cooperatives reported over 31,000 electrical poles destroyed due to the ice.  With about 20 poles per mile on an average electrical supply line, that results in over 1,550 miles of destroyed power supply capabilities, enough to stretch from Oklahoma City to New York City.  Electric power was not fully restored to all Oklahoma City residents until February 10, 11 days after the brunt of the ice storm exited the region.  Three weeks after the event, 2,320 customers remained without power. The most serious casualty in the wake of the ice storm, however, was the toll in human lives.  Seven fatalities were directly attributable to the effects of the late-January storm.  Four died in traffic accidents on the icy roadways, while two others died of asphyxiation while trying to get warm in enclosed spaces.  Another resident died when a large tree branch crushed him as he tried to clear his residence of debris.
  • December 3, 2002:  The third significant ice storm in as many years, this icy blast left a damage footprint in a narrow band from west central to north central Oklahoma. Areas north of the icing region generally received 2-6 inches of snow, with some areas reporting more than eight inches. Moderate to heavy rainfall occurred to the south. The main impact of the ice storm was damage to electrical distribution systems. Because much of the area impacted by the storm is rural, the primary victims of the storms were members of rural electric cooperatives (RECs). About 30,000 REC customers were without power for some time during the storm. According to the Oklahoma Association of Electric Cooperatives, REC losses were about $4.5 million. Other power suppliers were impacted also. At the storm's peak, about 25,000 Oklahoma Gas & Electric (OG&E) customers lost power.
  • January 12-15, 2007:  This storm caused catastrophic damage to the power systems in the eastern one-third Oklahoma, where ice accumulations were more than three inches in localized areas. Over 100,000 customers were without power at the height of this storm. One of the hardest hit areas was McAlester, where 15,000 lost power. Thirty-two deaths were linked to this storm:  19 perished in traffic accidents, eight succumbed to hypothermia, and three died due to accidental falls on the ice. Points northwest avoided catastrophic damage since most of the precipitation fell as snow and sleet.
]]> December 12, 2007 Fall 2007 Summary http://climate.ok.gov/ The Oklahoma Climatological Survey is proud to announce the Fall 2007 edition of its seasonal climate series "Oklahoma Climate," available online at: http://climate.mesonet.org/seasonal_summary.html.

Enjoy some stuffing with the following great stories:

  • A STRENGTHENING tropical system over Oklahoma? Yes, it occurred, and the Oklahoma Mesonet measured some astounding discoveries from the event.
  • A hundred years of fall, a hundred years of glorious weather...interrupted by some really inclement weather at times.
  • There is a mysterious globe hanging in the National Weather Center: UFO or teaching aid?
  • That pesky jet stream gives us a secondary severe season in the fall.
  • Our classroom exercise allows students to learn about evaporation and how to be better stewards of our fresh water supply.
  • Winter horticulture tips for lawn and garden enthusiasts.
  • An agricultural summary of the summer months.
  • A summer climate summary, including daily highlights.
  • Myths about flooding can be deadly. Stay safe by reading our own version of "Mythbusters"!
  • Our photo section shows the glory of fall...with a bias towards football fans.
]]> November 29, 2007 <![CDATA[1957 Is Still Safe]]> http://climate.ok.gov/ At one point this summer, 2007 looked poised to challenge 1957 as Oklahoma's wettest year on record. Bolstered by the wettest June since 1921, the statewide average rainfall through the end of July was more than eight inches above normal, and ranked as the third wettest such period on record. A strange thing happened as July faded on the calendar, however - the rains stopped. There were still deluges from time to time, of course. A rather indelible event will remain in Oklahoma's collective memory after a visit from an erstwhile Tropical Storm in September left 100-500 year rainfall amounts in west central and central Oklahoma. The flooding from that event was devastating, as were the rising waters of the spring and summer. Despite that dose of tropical moisture, Oklahoma returned to the dry pattern of the previous two years that saw drought ravage the state's winter wheat crop and diminish reservoir levels to some of their lowest on record. The August 1-November 20 period was the 22nd driest since 1921, about three inches below normal. The dryness varied across the state, but the southern tier of counties along with the Panhandle was hit the hardest, with drought designations from the National Drought Mitigation Center returning to the state for the first time since late March.

Central Oklahoma did manage to wrest away 1957's moniker as wettest year on record, however, with more than a month left in the year. As of November 20, Central Oklahoma had an average precipitation total of 49.60 inches for the year thus far, besting 1957's annual total of 49.14 inches.

Prospects for widespread precipitation look a tad underwhelming for the next few months. La Nina conditions have developed and strengthened in the equatorial waters of the south pacific, which could keep Oklahoma and the rest of the southern U.S. warm and dry though the winter months into early spring. An unfortunate consequence of the abundant rains of 2007 coupled with continued drying will be an increased risk of wildfires. Vegetation which grew at a rapid rate with the available moisture has now gone dormant and could act as a dangerous fuel source, should fires begin.

]]> November 20, 2007 <![CDATA[OCS Releases Climate Change Statement]]> http://climate.ok.gov/ Overwhelming observational evidence indicates that the earth is warming, and that the cause of that warming is mostly anthropogenic (caused by humans) in nature. Further, the vast majority of scientists that actually study climate change believe that warming will continue for the foreseeable future.

Of course, climate change has become a highly contentious topic in public discourse, with the waters being muddied by extreme viewpoints and concerns. So where does the truth lie, and what are the implications for Oklahoma? The Oklahoma Climatological Survey (OCS) has been mandated by the Oklahoma legislature to provide climate information and expertise which could be of value to the public, as well as to state policy- and decision-makers. In that regard, OCS has conducted a review of current assessments of climate change research in order to craft a definitive statement on global climate change and the implications for Oklahoma - detrimental and beneficial alike. The statement is based purely on the findings of the vast majority of scientists that study climate change.

]]> October 22, 2007 <![CDATA[Oklahoma City Sets Rainfall Record...In October!]]> http://climate.ok.gov/ A round of strong to severe thunderstorms associated with a cold front pushed Oklahoma City's rainfall total for the year to 53.34 inches according to the National Weather Service, and established 2007 as Oklahoma City's wettest year on record. This breaks the old record of 52.03 inches set in 1908 with more than two months left in the year. Oklahoma City records date back to 1891.

According to data from the Oklahoma Mesonet, the year-to-date statewide average rainfall total of 37.44 inches through October 15 ranks as the 6th wettest since 1921 at more than seven inches above normal. That is still well behind 1957's total of 42.66 inches for the same period. The Oklahoma Mesonet site at Minco has recorded 54.20 inches of rainfall since the beginning of the year to lead the state.

Central Oklahoma sits at more than 17 inches above normal for the January 1-October 15 period with an average total of 47.94 inches. That puts the central region at just about an inch behind its record annual total of 50.56 inches set in 1908.

]]> October 15, 2007 Monthly Climate Summary http://climate.ok.gov/ The September 2007 Monthly Climate Summary is now online at: http://climate.ocs.ou.edu/monthly_summary.html.

Highlights:

  • Another month, more flooding...but it's getting better.
  • The state was actually a bit dry as a whole. And warm, which should surprise nobody.
  • A Mesonet station recorded a low of 39 degrees!
  • A severe-weather injury occurred. Tornado? No. Flood? No. That leaves hail.
]]> October 10, 2007 Summer 2007 Summary http://climate.ok.gov/ The Oklahoma Climatological Survey is proud to announce the Summer 2007 edition of its seasonal climate series "Oklahoma Climate," available online at: http://climate.mesonet.org/seasonal_summary.html.

Enjoy these stories on a rainy day:

  • 100 years of summer in one magazine? Impossible...not!
  • Drought killed the 2006 wheat harvest. This year's rain had to help, right? Think again.
  • Squall lines are a major source of Oklahoma's annual rainfall total. We present an AWESOME climatology inside.
  • Do you open up all your windows when a tornado approaches? Well, don't. Read about other weather myths in this issue.
  • Our classroom exercise over soil moisture lets students get their hands muddy.
  • Fall horticulture tips for lawn and garden enthusiasts.
  • An agricultural summary of the spring months.
  • A spring climate summary, including daily highlights.
  • Stay safe in the wilderness with our camping safety tips!
  • Check out some photos of the terrible flooding across our state the past few months, taken by OCS employees.
]]> August 31, 2007 <![CDATA[Hurricanes on a Plain?]]> http://climate.ok.gov/ It's just not supposed to work that way. Tropical storms are not supposed to reform over land. Then again, with all the rain earlier this year, maybe it thought Oklahoma was the ocean. In what is about as rare of a weather event as anyone will ever witness, Tropical Storm Erin reformed over southwestern and central Oklahoma during the late afternoon and overnight August 18-19.

Shortly after 5 pm on Saturday, the remnants of Erin, which had been downgraded to a tropical depression, started to show signs of new life. Two brief tornadoes were reported in western Oklahoma, near Cordell. As the evening progressed, the storm continued to wrap up, bringing torrential rainfall across southwestern Oklahoma and slowly spreading eastward and northward across the state. Beginning at 1:15 am on the 19th the Mesonet (http://www.mesonet.org) site at Watonga, near the center of the circulation, reported severe winds nearly continuously for two hours. During this time, sustained wind speeds over 40 miles per hour were reported. Had that occurred over open water, Erin would have been upgraded to a tropical storm. Wind gusts over 70 miles per hour were recorded at the Watonga and Fort Cobb Mesonet sites, and the Watonga Airport topped the list with an 82 mph gust.

Erin continued to wrap up during the overnight hours, eventually forming a new eye, centered just north of El Reno at about 5 am. The circulation persisted for several hours, driving bands of moisture counter-clockwise around the eye. The slow-moving system dropped more than five inches of rainfall along its path, with over an inch common in a larger area from Erin's outer 'bands'. Of the Mesonet sites, Fort Cobb picked up the highest total - 9.24 inches. However, a CoCoRaHS (http://www.cocorahs.org) observer reported 11.00 inches northwest of Geary, noting "the amount was MORE than 11 inches. When I went out to check the gauge this morning, it was full, had clearly overflowed during the night, and I spilled some of the contents getting the gauge off the post. The majority of the rain occurred between 11 pm and 4 am."

Oklahoma has a long list of natural hazards we face year-in and year-out. Now it looks like we can add tropical storms to the list. It will be interesting to see whether our sure-to-be disaster declaration will be labeled as such, or get lost amongst the many other "severe storms and flooding" events in our history.

The rainfall added by Erin was yet another blow to an already water-slogged state, especially for central Oklahoma. Rainfall totals averaged over the central Oklahoma region stands at 43.14 inches since the beginning of the year, 19.09 inches above normal - easily the wettest on record for the area. The previous mark was set in 1957 with a January 1-August 20 total of 36.90 inches. Statewide, the year thus far is the 4th wettest on record with 31.96 inches, 8.42 inches above normal.

The summer season through August 20 is the wettest on record statewide with a total of 15.46 inches, 6.71 inches above normal. Central Oklahoma is 14.45 inches above normal for the June 1-August 20 period with 23.23 inches of rainfall.

To watch Tropical Storm Erin as it moved across Oklahoma, download WeatherScope from our Software (http://climate.ok.gov/software/) website and then click here

Oklahoma's previous bouts with tropical systems
Year Month Tropical Storm South Region Comments
1996 September Fausto Pacific6+ inches rain; minor flooding
along North Canadian.
1995 August Dean Gulf of Mexico12-16 inches in parts of OK;
interacted with weak, stalled
cold front; major flooding
along much of Salt Fork of
the Arkansas River in Grant
and Kay Counties; flooding
also occurred on Cimarron,
Washita and Arkansas Rivers.
1988 September GilbertGulf of MexicoInteraction with slow-moving
front; 4+ inch rains fell onto
saturated soils; flooding on
creeks and rivers.
1986 September-
October		 PainePacificUp to 20 inches in north-central
OK; massive flooding on
Cimarron. flooding on the
Arkansas River; ground was
already saturated by rainfall
associated with remnants of
Pacific Hurricane Newton;
estimated damages of $350
million; 52 counties declared
disaster areas.
1983 October TicoPacificUp to 17 inches rain in southwest
and central OK; Red River at
Burkburnett and Terral rose to
highest stage in 60 years;
widespread flooding of smaller
rivers and creeks.
1981 October NormaPacificUp to 24 inches of rain in
south-central OK (Monthly total
of 25.8” at Madill is greatest for
any station during any month in
OK history).
1961 September CarlaGulf of MexicoUp to 9 inches of rain fell across
central and north central
Oklahoma.
1900 September UnnamedGulf of MexicoThe remnants of the hurricane
that devestated Galveston
inundated eastern Indian
Territory with flooding rainfall.
]]> August 20, 2007 <![CDATA[The Short, Hot Summer]]> http://climate.ok.gov/ Mother Nature launched a dastardly and unprovoked attack on our cool summer, and now she has set her sights on our wet summer as well. Prior to August 5, the 119 Oklahoma Mesonet sites had recorded triple-digit temperatures three times. In the 10 days between August 5 and August 14, however, those same sites have recorded temperatures of at least 100 degrees 390 times. The statewide average temperature for August 1-14 was 82.0 degrees, 1.4 degrees above normal. The statewide average high temperature, which has been creeping up daily, was 96.1 degrees for the same time period. Nighttime temperatures have been inching downward as the state begins to dry out and the length of daylight hours decreases. Through those 14 days, the average nighttime temperature was 2.1 degrees above normal. Temperatures normally reach a high of around 94 degrees in mid-August, decreasing steadily to around 90 degrees at the beginning of September. The highest temperature in the state thus far has been 106 degrees recorded at the Hooker and Webbers Falls Mesonet sites on August 12 and 13, respectively. That's a far cry from the summer's coolest high temperature of 67 degrees, recorded at Boise City way back on June 14. It could be worse; for the same period in 2006, the Mesonet had recorded triple-digit temperatures 1079 times, with a high of 109 degrees twice.

Since the 100-degree temperatures ramped up in earnest on August 5, Oklahoma has recorded a measly 0.05 inches of rainfall on average statewide. In fact, as of the morning of August 15, the statewide average precipitation for the month thus far was 0.30 inches, more than an inch below normal and the 8th driest such period since 1921. Most of that rainfall occurred at a few locations. Slapout received 3.2 inches during that period while Byars had three inches. Nearly 50 of the Oklahoma Mesonet's 119 stations recorded no rainfall during those 15 days. The statewide average for the 30-day period from July 16-August 14 was 1.05 inches, which is the 10th driest such period on record. That is contrasted with the 60-day period from June 16-August 14, where the statewide average was 10.49 inches, more than four inches above normal and the 5th wettest on record.

]]> August 16, 2007 <![CDATA[The Heat Is On]]> http://climate.ok.gov/ Oklahoma's flirtation with a Canadian-style summer came to a crashing halt as triple-digit temperatures replaced the flooding rains of June and July. The main culprit in the journey back to normalcy is an upper-level ridge of high pressure that has become entrenched over the Southern Plains. The ridge has effectively stifled the widespread rains that the state saw for much of the summer and at the same time allowed temperatures to soar into the 100s with increasing frequency. Prior to August, the Oklahoma Mesonet's 117 observing stations had recorded only three 100-degree temperatures, the highest of which was 103 degrees at Goodwell on July 8. Those same 117 stations have recorded temperatures of more than 100 degrees 37 times between August 5 and August 8. Most of those extreme temperatures have occurred in extreme western Oklahoma and the Panhandle, which have been drier than points east. The highest temperature in the state, through August 8, has been 105 degrees at Buffalo, reported both on August 7 and August 8.

The upper-level ridge made the return to of Oklahoma's normal summertime weather an inevitability - heat, heat and more heat. The abundant precipitation of the previous two months have helped keep air temperatures down somewhat as the sun's rays work primarily to evaporate moisture from the surface. As the surface begins to dry, however, and vegetation loses its greenness, more of the sun's energy will be used to heat the ground. The heat that western Oklahoma has been seeing will begin to creep eastward, spreading eastward across the state.

Unfortunately, as the moisture from the ground is evaporated, it increases the humidity of the air near the surface. This adds to Oklahoma's normal hot and humid August conditions. Heat indices have been in the 105-110 degree range across portions of northern Oklahoma, prompting excessive heat warning and heat advisories from the National Weather Service.

A current heat index map from the Oklahoma Mesonet can be found at: http://www.mesonet.org/data/public/mesonet/maps/realtime/current.heat.gif

]]> July 17, 2007 <![CDATA[100 Degrees, We Hardly Knew Ye]]> http://climate.ok.gov/ Incredibly, only three triple-digit temperatures have been recorded by the Oklahoma Mesonet's 119 observing sites during 2007. Of the nearly 12,000 high temperature observations reported by the network, the lone 100-degree readings were: 103 degrees at Goodwell on July 8; 101 degrees at Hooker, also on July 8; 100 degrees at Tipton on June 19. Results from previous years indicate that 2004 had the next-lowest total through July with 117 reports of triple-digit temperatures from the Mesonet. The highest total of 2520 came during the drought-induced heat of 1998. Last year's total through July was 1565.

Oklahoma's cool and wet summer continued through July according to preliminary data from the Oklahoma Mesonet. The statewide average temperature for the month was three degrees below normal to rank as the 11th coolest July since 1895. Cool summer months are normally associated with above normal precipitation and that was exactly the case this July as well. The statewide average rainfall totaled nearly four inches, more than an inch above normal, to rank as the 24th wettest July on record. The greatest area of surplus precipitation occurred from the southeastern tip of the state up through central Oklahoma. The southeast led the state with an average of more than eight inches, nearly five inches above normal - the 4th wettest July for that area.

This year's June-July period ranks as the wettest on record for the state with a surplus of more than six inches. Central Oklahoma led the state with a surplus of more than 11 inches. The Panhandle, on the other hand, was more than an inch below normal and experienced its 23rd driest June-July on record. Central Oklahoma had its wettest January-July on record with a total of 38.52 inches, nearly 16 inches above normal. Statewide, the June-July period ranks as the 13th coolest on record, more than two degrees below normal. The year thus far ranks as the 53rd coolest.

July 2007 Mesonet Statistics
Climate DivisionAvg TempDepartureRankRainfallDepartureRank
Panhandle77.7-1.932nd Coolest1.67-0.8531st Driest
North Central78.9-3.312th Coolest3.100.1252nd Wettest
Northeast78.9-2.028th Coolest3.05-0.1157th Driest
West Central78.1-3.68th Coolest2.390.2649th Wettest
Central79.1-2.919th Coolest5.693.1210th Wettest
East Central78.6-2.718th Coolest5.122.1423rd Wettest
Southwest79.3-3.97th Coolest1.93-0.2553rd Driest
South Central79.0-3.77th Coolest4.792.2514th Wettest
Southeast78.1-2.88th Coolest8.404.824th Wettest
Statewide78.7-2.911th Coolest4.031.2924th Wettest

]]> August 2, 2007 <![CDATA[Statistics to Ponder]]> http://climate.ok.gov/ How wet is it? Or is the real question "how dry was it?" Comparing the drought of the previous two years to the flooding rainfall of 2007 is indeed like comparing apples and oranges, with one notable exception - both hazards have been disastrous for those affected. The 2006 wheat crop was decimated by drought while the 2007 crop languished in fields too wet for machinery. The drought conditions of 2005 and 2006 spawned destructive wildfires while the torrential rains of this year have flooded homes and businesses across the state. The most unfortunate similarity is the cost in lives, however, whether it be those who were lost fighting wildfires or to the rising floodwaters. With those similarities noted, the statistics between the two periods could not be more striking.

According to data from the Oklahoma Mesonet, the statewide average rainfall through July 16 has already eclipsed the yearly rainfall amounts of both 2005 and 2006. The statewide average rainfall for the year thus far, through July 16, is 29.05 inches. The yearly totals for 2005 and 2006 were 26.93 inches and 28.59 inches, respectively.

The regional averages are even more outlandish. Central Oklahoma currently leads the state with an average of 37.76 inches - the wettest on record for that part of the state, 16.65 inches above normal. Compare that with identical periods from 2005 and 2006 when the averages were just 16.85 inches and 14.13 inches, respectively.

As a final exclamation point, consider the rainfall statistics from the Oklahoma Mesonet site at Minco, which has recorded 44.00 inches of precipitation through July 16. The same periods from 2005 and 2006 combined added up to 23 inches, a little more than half of this year's total. In fact, to match this year's total, you have to go back all the way to February 24, 2005 - that's February 24, 2005, through December 31, 2006. In other words, it took the rainfall from the previous 676 days at Minco to match this year's total accumulated in 197 days.

]]> July 17, 2007 <![CDATA[Seattle, Oklahoma?]]> http://climate.ok.gov/ Oklahoma City might be considering changing its name to Seattle, given how much rain we've had recently. Friday morning's rains mark 17 consecutive days of rainfall in Oklahoma City, according to the National Weather Service. This breaks the previous record of 14 consecutive days, from May 29 through June 11, 1937. Although, if we went farther back in history, we hear the real record is 40 days (and nights)! Then again, maybe we're just trying to convince the Seattle Supersonics basketball team to move to Oklahoma City.

Since the most recent rounds of rainfall began in Oklahoma on May 24, the state has tallied 9.42 inches of rain (through June 27), on average, which is more than four inches above normal for the period. Central Oklahoma leads the way with an average of 13.38 inches. Now anybody who deals with Oklahoma weather knows that things are rarely average - some places get more and some get less. The "more" side of it totals as much as 19.72 inches at Minco and more than 18 inches at Marena, Medicine Park, Apache, Chickasha and Kingfisher.

All this rain makes it kind of hard to remember how dry it had been. When you figure the rain total for the last 365 days, it comes up just a bit above average. Southwest, west central, and central Oklahoma come up on the wet side and southeast comes up a bit below normal, with the state overall showing a surplus of 3.94 inches. The recipe? Take about 6 really dry months, about 3-4 near-normal months, and a couple of incredibly wet months and you have "normal," just like you would expect in Oklahoma!

Track your rainfall at http://climate.mesonet.org/rainfall_update.html

May 24, 2007 through June 27, 2007
Region Total
Rainfall		 Departure
from Normal		 Percent of
Normal		 Rank since
1921 (of 87)		 Wettest
on Record
Panhandle 3.16" -0.35" 90% 35th driest 7.90" (1962)
N. Central 8.77" +4.01" 184% 6th wettest 11.94" (1957)
Northeast 10.76" +5.18" 193% 5th wettest 13.84" (1957)
W. Central 7.32" +2.58" 154% 9th wettest 10.36" (1995)
Central 13.38" +7.81" 240% 1st wettest 12.41" (1957)
E. Central 8.56" +2.67" 145% 11th wettest 12.44" (1935)
Southwest 9.21" +4.19" 183% 4th wettest 11.20" (1987)
S. Central 12.80" +7.18" 228% 1st wettest 11.07" (1987)
Southeast 8.72" +2.85" 149% 12th wettest 11.87" (1935)
Statewide 9.42" +4.24" 182% 2nd wettest 9.79" (1957)

]]> June 29, 2007 <![CDATA[Our Cup Runneth Over]]> http://climate.ok.gov/ After two years of severe drought, Mother Nature turned the spigots on in relief but seems to have forgotten to shut them off. Consequently, flooding has become the hazard of choice during the past three months. Oklahoma's statewide average precipitation total for the year thus far ranks as the 19th wettest since 1921, 1.40 inches above normal. Much of that bounty is buoyed by the northwestern half of the state. The north central, central and west central regions are all experiencing year-to-date totals ranked within the top-ten wettest. The last 90 days have been particularly wet, with the state enjoying its 13th wettest such period. West central, central, and north central totals are all ranked in the top-six wettest during that same time frame. Not all areas of the state are sharing in the moisture surplus, however. The eastern third of the state has continued to dry out over similar periods. The southeast and east central sections of the state are nearly three inches below normal since the beginning of the year to rank as the 26th- and 29th-driest on record, respectively. The two-year precipitation statistics reflect the just-broken drought with virtually the entire state, save for the west central section, showing precipitation deficits. May 2005-May 2007 for southeastern Oklahoma is the driest such period on record.

It's somewhat standard for Oklahoma's severe drought episodes to end with a deluge instead of a trickle. The state's most notable droughts, the 1930s Dust Bowl and the 1950s, were both broken in a spectacularly wet fashion. The Dust Bowl episode was whittled away in early 1941 before being blasted from existence by a statewide average rainfall of 11.32 inches in October, the wettest Oklahoma month on record. The 1952-57 drought, considered the state's worst statistically, ended rather abruptly in May 1957 with heavy rains and major flooding on the state's largest river systems. That year still stands as the wettest in Oklahoma history at 48.21 inches.

]]> May 30, 2007 Spring 2007 Summary http://climate.ok.gov/ The Oklahoma Climatological Survey is proud to announce the Spring 2007 edition of its seasonal climate series "Oklahoma Climate," available online at: http://climate.mesonet.org/seasonal_summary.html.

Enjoy these stories on a rainy day:

  • In Oklahoma's centennial year, we celebrate 100 years of Oklahoma spring.
  • There's a new Fujita Scale in town. Twist when you say that, stranger!
  • Our classroom exercise exposes students to a tornadoes lesser-valued cousin...the straight-line severe wind.
  • Oklahoma Mesonet sites move to the big city.
  • Does our friend El Nino give us more tornadoes? How about La Nina? Find out in this issue.
  • Our photo section showcases a different "EF" scale...the "ef"florescence of Oklahoma.
  • Learn how to program your weather radio to avoid all those pesky warnings from several counties away.
  • Summer horticulture tips for lawn and garden enthusiasts.
  • An agricultural summary of the winter months.
  • A winter climate summary, including daily highlights.
]]> May 16, 2007 <![CDATA[Flood Awareness Month]]> http://climate.ok.gov/ Governor Brad Henry proclaimed May as Flood Awareness Month, and apparently not a day too soon. In just the first eight days of May 2007, Oklahoma posted a statewide-averaged rainfall total of 3.53 inches. By comparison, May 2006 only recorded 3.03 inches - for the entire month. The normal May rainfall is 5.21 inches. In short, it took only eight days to surpass the total from the drought-plagued month of May 2006.

This rain comes on the heels of a wet April, which helped Oklahoma erase the last vestiges of a 2-year-long drought. On April 3, the U.S. Drought Monitor ended drought designations, although lingering effects still remained in pastures and reservoirs. With the May rainfall, the reservoir issue has nearly been resolved. Lake Thunderbird near Norman, which just a few weeks ago was nearly 30% below it's normal conservation level, is now nearly full. Lake Altus-Lugert, which had been less than half-full, is three-quarters full, great news for cotton-growers in southwest Oklahoma that rely upon the irrigation lake in the summer.

If there was any doubt about the recovery from drought in Oklahoma, this past week has put that to rest. Soil moisture at nearly every Mesonet site is saturated, the Keetch-Byrum Drought Index is virtually zero statewide and wildfire potential is almost non-existent. In the last 30 days, the driest part of the state (the Panhandle) has 114% of normal rainfall. Statewide rainfall totals place Oklahoma as the 7th wettest on record over the past 30 and 60 days and the 13th wettest year-to-date (through May 8). Even more incredible, every region of the state except the northeast is at or above normal for the water year (beginning October 1), and the northeast missed by only 0.03 inch. Oklahoma has not experienced a Spring like this since 1999.

As so often occurs in Oklahoma, we switched from one hazard to another. Instead of fighting wildfires, Oklahomans must now remember safety rules for floods. According to the National Weather Service, "each year, more deaths occur due to flooding than from any other thunderstorm related hazard. Why? The main reason is people underestimate the force and power of water. Many of the deaths occur in automobiles as they are swept downstream. Of these drownings, many are preventable, but too many people continue to drive around the barriers that warn you the road is flooded. Whether you are driving or walking, if you come to a flooded road, Turn Around Don't Drown. You will not know the depth of the water nor will you know the condition of the road under the water."

Earlier, Governor Henry proclaimed March as "Flood Insurance Month," part of a state campaign to spread the word about the availability of affordable flood insurance through the Federal Emergency Management Agency's National Flood Insurance Program (NFIP). According to the Oklahoma Water Resources Board, Oklahoma currently boasts 376 NFIP member communities, which consist of municipalities, counties, and tribes. Gavin Brady, State Floodplain Manager, notes that "implementation of sound floodplain management and building strategies, particularly through the NFIP, is the most effective way for communities to avert potential flood damages." However, he encourages communities to go "above and beyond" minimum NFIP standards, consistent with the national Association of State Floodplain Manager's ongoing 'No Adverse Impact' initiative. Brady points out that 87% of homes in Oklahoma's designated floodplains have no flood insurance.

As we continue to monitor rainfall patterns, we should pause and realize how vulnerable we remain to the effects of water, both too little last year and too much now. Water management is a critical issue for Oklahoma, both in managing excess to limit damages and preserving sufficient resources for the dry times. Climate change scenarios suggest that this will only get worse in coming decades. All Oklahoma citizens are encouraged to participate through local community planning and through the state's Comprehensive Water Plan process, to assure that we will become less vulnerable to these risks in the future.

]]> May 9, 2007 <![CDATA[Spring Tornadoes and ENSO?]]> http://climate.ok.gov/ Ashton Robinson Cook: Storm Prediction Center SCEP student

Spring can be the most violent season for Oklahoma weather. With spring in full swing, Oklahomans may be wondering about the prospects of the upcoming tornado season and whether El Niño or La Niña can increase or decrease probabilities of a tornado in an area.

El Niño and La Niña are part of a more complex climate system termed El Niño Southern Oscillation (ENSO). This climate phenomenon is driven by abnormal sea surface temperatures in the equatorial Pacific, with shifts in weather around the entire world attributed to ENSO. El Niño is the warm phase of this climate phenomenon, denoted by abnormally warm sea surface temperatures. La Niña is the opposite; it involves significantly cooler than average sea surface temperatures in the region. The third ENSO phase, Neutral, indicates sea surface temperatures that are near the climatologically normal level.

ENSO has its most pronounced effects on U.S. weather during the winter months. In a winter El Niño, warming of the equatorial sea surface temperatures forces a stronger than average subtropical jet to develop across the southern tier of the U.S. The jet tends to bring cooler, wetter conditions to the southern tier of states, including Oklahoma. In contrast, winter La Niña conditions tend to diminish the presence of the subtropical jet and displace it farther to the north. Generally, this results in drier, warmer conditions in Oklahoma. Although the effects are less clear during the spring months, cooler and wetter conditions generally prevail throughout the spring in El Niño months, with drier conditions noted during La Nina and Neutral months.

So are there similar shifts noted in spring tornado activity?

There is very little evidence that ENSO is responsible for shifts in spring tornado activity in Oklahoma. A brief analysis of tornadoes occurring in Oklahoma during spring and early summer (April, May, and June) between 1950 and 2005 reveals only very small shifts in tornadic activity across the state. Figures 1 and 2 indicate that some of the tornadoes during the La Nina phase seem to have longer tracks compared to tornadoes in El Niño phase events, especially across central and northern Oklahoma. Although the shift is evident, it is not very pronounced. Tornadoes occur in all parts of the state regardless of ENSO phase. In addition, it is difficult to determine a solid meteorological basis for this shift as distinct shifts in weather patterns (such as the climatological positions of jet streams, fronts, and drylines) during the spring months have not been determined.

A further analysis reveals that stronger tornadoes (rated F2 or higher in the Fujita Scale) occur slightly more frequently in the La Niña phase of ENSO (30.9%) compared to the El Niño phase (21.6%). While strong tornadoes are also a more frequent occurrence in Neutral phases (29.6%), it is difficult to draw valuable comparisons between Neutral ENSO phases and others because the Neutral phase occurs nearly twice as often (28 spring seasons) as both El Niño (13 spring seasons) and La Niña phases (15 spring seasons). As expected, the Neutral phase contains nearly double the tornadoes (1015) that either the La Niña (525) or El Niño phase (547) contains, indicating that the frequency of tornadoes across Oklahoma is not affected by ENSO phase.

In short, it appears that the effect of ENSO on spring Oklahoma tornado activity is minimal. The entire state has equal chances of experiencing tornadoes regardless of the ENSO phase. While stronger tornadoes occur less frequently in the El Niño phase compared to other phases, strong and even violent tornadoes (rated F4 or F5) have been observed in all three phases.

Figure 1: Oklahoma tornadoes during the EN phase. Graphic created using Severe Plot v. 2.0 (Hart and Janish 1999)

Figure 2: Oklahoma tornadoes during the LN phase. Graphic created using Severe Plot v. 2.0 (Hart and Janish 1999)

Figure 3: Oklahoma tornadoes during the N phase. Graphic created using Severe Plot v. 2.0 (Hart and Janish 1999)

Sources:

Hart, J. A., and P. Janish, 1999: Severe Plot v. 2.0 Oklahoma Climatological Survey: http://climate.ok.gov
NOAA Climate Prediction Center: http://www.cpc.noaa.gov
Schaefer, J.T., and R. Edwards, 1999: The SPC Tornado/Severe Thunderstorm Database. Preprints, 11th Conf. Applied Climatology, Amer. Meteor. Soc., Dallas, TX ]]> April 26, 2007 <![CDATA[Mesonet Featured at State FFA Convention]]> http://climate.ok.gov/ The Oklahoma Mesonet is participating in the annual FFA state convention at the Cox Convention Center in Oklahoma City, April 24-25. Oklahoma FFA assists students interested in careers in more than 300 areas, ranging from agri-science to biotechnology to turfgrass management. The convention attracts thousands of students from all counties in the state. One stop in the exhibit hall is the Oklahoma Mesonet booth, where Al Sutherland and Laura McKay will be demonstrating how weather information is harnessed to help the state's agricultural industry deal with Oklahoma's weather.

Weather is no longer something that farmers and ranchers passively accept. Through technological advancements, they are now able to continuously monitor weather conditions on the local level and apply it to their practices. Results include increased production, reduced pesticide and fertilizer costs, and environmentally-friendly practices. One of the tools they use is the Mesonet's AgWeather page, http://agweather.mesonet.org/. AgWeather combines real-time information from the Oklahoma Mesonet with a variety of agricultural application models, market information, and Oklahoma State University Extension fact sheets to provide a comprehensive source of information for all varieties of businesses. We invite you to visit with Al and Laura at the booth, or to stop by the AgWeather website.

]]> April 23, 2007 <![CDATA[Two <q>Natural Hazards</q> Conferences]]> http://climate.ok.gov/ Oklahoma faces a wide variety of natural hazards. One of these, heat stress, will be highlighted in two events this week.

On Tuesday, April 17, the "Never Leave Your Child Alone" news conference will focus on heat deaths resulting from leaving children unattended in automobiles. The Oklahoma City Fire Department, Safe Kids Worldwide, and General Motors are teaming up on an information campaign this summer to draw attention to what is an easily presentable cause of death. Since 1998, at least 11 Oklahoma children have died from heat stroke when left unattended in closed vehicles, some for as short as only a few minutes. Even when the temperature is as low as 70 degrees, the temperature inside a vehicle can rise 19 degrees in just 10 minutes. Children are especially vulnerable, because their body temperatures rise at a rate of three to five times faster than an adult's. The news conference will occur at 3 p.m. at the Oklahoma City Police/Fire Training Center, 800 N. Portland. For further information, contact Tony Young with the Oklahoma City Fire Department, (405) 297-3314.

On Wednesday, April 18, hazards will be the topic of a day-long conference held at the National Weather Center. The second "Climate & Loss Mitigation Conference", hosted by the Oklahoma Insurance Department, will feature speakers and breakout sessions focusing on climate-related hazards, how those might change because of global warming, what impacts this might have on the insurance industry, and things we can do in our communities to make ourselves less vulnerable to both projected hazards and the hazards we already face. Registration is as low as $15 for seniors and students or $30 for the general public, and includes lunch. The conference is co-sponsored by the Oklahoma Climatological Survey, State Farm Insurance, and American Farmers and Ranchers Insurance. Additional information is posted at http://www.oid.state.ok.us/ or call (405) 325-2541. ]]> April 16, 2007 Return of Deadly Tornado Ends Record Absence http://climate.ok.gov/ The two confirmed tornado deaths on March 28 near the small town of Elmwood in Beaver County are the first in the state since April 11, 2001, according to statistics from NOAA's National Climatic Data Center. The nearly six-year span of 2178 days is the longest interval between killer tornadoes since accurate statistics began in 1950 and eclipses the previous record of 1457 days, which occurred between May 7, 1995, and May 3, 1999. The fatalities mark the first official tornado deaths in Beaver County, although additional records list a fatality near Balko in Beaver County on May 20, 1949. Beaver County's last tornado occurred on September 21, 2006 near Turpin.

Oklahoma's last tornado fatality occurred four miles east of Coalgate in Coal County a little after 4:30 pm on April 21, 2001, after a mobile home was thrown 200 yards and disintegrated, killing one. Oklahoma's 3028 tornadoes since 1950 have resulted in 265 deaths, over 4000 injuries and more than $3 billion in damage. The state's 27 tornadoes during each of the last two years are little more than half the annual average of 53.

]]> March 29, 2007 Heavy Rains Fall in Oklahoma http://climate.ok.gov/ Heavy rainfall in the northern one-third of the state has helped ease severe drought conditions in north central Oklahoma. The Oklahoma Mesonet site at Foraker recorded 5.31 inches of rainfall during the event, with 5.14 inches of that total occurring on the 20th. General amounts between 3-5 inches fell in Grant, Kay, Noble, and Osage Counties. Unofficial reports and radar estimates of 6-7 inches came in from the Newkirk and Red Rock areas. Flash flood warnings were issued by the National Weather Service for Kay and Noble Counties due to the heavy rains. Roads in and around Blackwell, Newkirk and Ponca City were reported under water on the 20th.

Much of north central Oklahoma remains in severe drought conditions according to the National Drought Monitor. The rest of the western half of the state is categorized as abnormally dry or in moderate drought conditions.

]]> March 23, 2007 Emergency Managers Course http://climate.ok.gov/ The Oklahoma Climatological Survey is conducting a workshop for public safety officials. The Spring Full Certification Course is March 13-16, 2007 at the National Weather Center in Norman. Completion of this course will deem the student as a Full Participant in OCS's OK-First program. ]]> March 12, 2007 Grand Prize Winner http://climate.ok.gov/ Dr. Matthew Haugland and Dr. Ken Crawford met with the Governor Brad Henry and Lieutenant Governor Jari Askins at the Oklahoma State Capital to honor Dr. Haugland for winning the Grand Prize at the National Collegiate Inventors Competition. The National Collegiate Inventors Competition recognizes and rewards innovations, discoveries and research by college and university students and their faculty advisers. Haugland's entry, titled "The Uncoupled Surface Layer Model," is based on his research of weather observations in microclimates. The Grand Prize carries a monetary value of $25,000 which Dr. Haugland intends to use to start his own private company based in Oklahoma.

]]> February 16, 2007 Winter 2006-2007 Summary http://climate.ok.gov/ The Oklahoma Climatological Survey is proud to announce the Winter 2006-07 edition of its seasonal climate series "Oklahoma Climate," available online at: http://climate.mesonet.org/seasonal_summary.html.

Thaw out with these stories:

  • In Oklahoma's centennial year, we celebrate 100 years of Oklahoma winters.
  • NOAA weather radios are being distributed to schools around the state to keep your kids safe.
  • A recap of the National Weather Festival, held at the new National Weather Center.
  • Our classroom exercise exposes a little-known but very valuable variable: the wet-bulb temperature.
  • Bringing drought monitoring into the 21st century.
  • Our photo section showcases the adorable kids of OCS employees enjoying this year's Winter Wonderland.
  • Home heating tips -- protect your family while staying warm.
  • Spring horticulture tips for lawn and garden enthusiasts.
  • An agricultural summary of the fall months.
  • A fall climate summary, including daily highlights.
]]> February 22, 2007 The Long Winter http://climate.ok.gov/ If this has seemed like a long, cold winter, that's because it has been. OCS and KWTV News9 looked at past winters to see just how this winter compared. Digging back through snowfall records for Oklahoma City from 1948 to present, we've learned just how this winter stacks up to some of the memorable ones from the past.

Even though this winter has been cold (38.9 degrees average temperature from December 1 - February 15), it is far from the coldest. In fact, of the past 60 years, this year is so far tied for 29th coldest - roughly the middle of the pack. However, it may seem colder because Oklahoma City just came off its 3rd warmest winter on record, a balmy 43.2 degree average temperature. You have to go back to 2000-2001 for a colder period, when the average temperature was a chilly 35.0 degrees.

But cold is only part of the story. If it seems like we've had more snow or ice events or the snow/ice has stuck around longer than usual, that is indeed the case. As of February 15, Oklahoma City reported 19 snow days (days with at least 1 inch of snow falling or on the ground). This ties for the 5th most since 1948, and there are still another 4-6 weeks in which additional snow may be possible. The record is 25 days, set in 1948.

The snow/ice also has stuck around longer. The 13 days from January 12-24 where snow (or ice) either fell or was on the ground is the 3rd longest period of consecutive snow-days in modern records. The longest period was 18 days in 1978.

So this winter has definitely been tough, but what was the worst winter? Hands-down, that distinction goes to 1978-1979. That winter was the coldest (30.4 degrees), 2nd for the most number of snow days (23), had 6 snow events, and had 18 consecutive days with snow on the ground. This came right on the heels of the winter of 1977-1978, which otherwise would have been considered the worst winter in modern times. As spring came in 1978, folks were probably grateful to have that winter put behind them, but they had no idea that it could get worse just one year later.

]]> February 16, 2007 OCS Speaks at The Big Read http://climate.ok.gov/ The National Weather Center will host a kick-off event for the Pioneer Multi-County Library System's Big Read event, featuring "The Grapes of Wrath" by John Steinbeck, on Friday, Feb. 9. Scientists will give talks, followed by a reception and tours of the NWC facility, located at 120 David L. Boren Blvd. Geographers and meteorologists from the College of Atmospheric and Geographic Sciences will discuss weather conditions of the Dust Bowl compared with today, accuracy of the conditions portrayed in the book, human impact and farming practices during the Dust Bowl and how these issues affect us today.

Speakers include Gary McManus, a climatologist from the Oklahoma Climatological Survey. Gary will discuss the climate of the Dust Bowl era, and the conditions and practices that led to the Dust Bowl disaster.

John Steinbeck's The Grapes of Wrath is not merely a great American novel. It is also a significant event in our national history. Capturing the plight of millions of Americans whose lives had been crushed by the Dust Bowl and the Great Depression, Steinbeck awakened the nation's comprehension and compassion.

Visit the Big Read website at http://www.bigreadok.com for more information, including registration, online discussions, and updates leading up to the event. Registration for this event is limited to 500. Due to the demand, the presentation in the auditorium will be presented twice: 5:45 and 6:45 p.m. ]]> February 5, 2007 State Climatologist to Speak on Climate Change http://climate.ok.gov/ Global warming may be the furthest thing from our minds these days, but just a few months ago, it felt very real. State Climatologist Ken Crawford will join climate experts on a panel discussion focused climate change and its implications for Oklahoma. The panel will discuss the current scientific understanding of the dominant causes of climate change and its effects locally, nationally and internationally. This coincides with the February 2 release of the first volume of the Intergovernmental Panel on Climate Change (IPCC) fourth assessment report, "Climate Change 2007: The Physical Science Basis".

Dr. Crawford, Regents Chair Professor of Meteorology at The University of Oklahoma, will be joined by renowned climate experts Dr. Robert Corell, Director of Global Change Programs at the Heinz Center in Washington, DC, and Dr. David Karoly, Williams Chair Professor of Meteorology at the University of Oklahoma. Dr. Corell served as the Chair of the Steering Committee for the Arctic Climate Impact Assessment, an international effort completed in 2005 to evaluate the effects of climate variability and climate change in the Arctic. Dr. Karoly was a lead author and review editor of the forthcoming IPCC report. Also appearing on the panel will be Dr. Mark Shafer, Director of Climate Information from OCS, who will look at climate change from a political and policy perspective.

The IPCC report assesses current scientific knowledge of the natural and human drivers of climate change, observed changes in climate, the ability of science to attribute changes to different causes, and projections for future climate change. Panel members will each give a short presentation, followed by a question-and-answer period. Please join us on Friday, February 2, at 1:30 p.m. at the National Weather Center in Norman. For accommodations based on disability, or more details, please contact the School of Meteorology at (405) 325-6561. ]]> January 30, 2007 Ice Storm! http://climate.ok.gov/ Freezing rain is a distinct wintertime hazard in Oklahoma. Ice storms are extended freezing rain events, lasting several hours to days at some locations, wit