February and Winter 2010 Highlights

February 2010 and

Winter (Dec-Jan-Feb) 2009-10

February 2010

Tulsa: February 2010 was 13th coldest (36.2°F, since 1905), 39th wettest (2.03", since 1888), and tied with 1949 as the 35th snowiest (2.4", since 1900) February on record.

Tulsa: This is the first February since records began in 1905 that the Tulsa high temperature did NOT reach 60 degrees.

Tulsa: February 2010 ranked as 13th for the greatest number of heating degree days (798) in the month of February since records began in 1905. Out of the top 20 highest number of heating degree days in February, the most recent one prior to this year was in 1989.

Fort Smith: February 2010 was the 14th coldest (37.9°F), 21st snowiest (4.0"), and 48th driest (1.70") February since records began in 1882.

Fort Smith: A daily record snowfall of 4.0" tied on 02/08/2010. The previous record occurred in 1929.

Fort Smith: February 2010 tied with 1958 and 1980 as 14th for the greatest number of heating degree days (750) in the month of February since records began in 1882. Out of the top 20 highest number of heating degree days in February, the most recent one prior to this year was in 1989.

Despite being in the top 15 coldest Februarys on record in Tulsa and Fort Smith, no daily temperature records were set in February 2010. No daily temperature records were set McAlester and Fayetteville as well.

Southeast Oklahoma remains in a wet period this month. According to the Oklahoma Climatological Survey (OCS), southeast OK ranked as the 2nd wettest Cool Growing Season to date (Sep. 1, 2009-Feb. 28, 2010) and 3rd wettest Last 365 day period (March 1, 2009-Feb. 28, 2010) since records began in 1921.

A 4.1 magnitude earthquake occurred on Feb. 27, 2010 at 4:22 pm CST near Sparks, OK (about 45 miles east of Oklahoma City). This earthquake was felt across the Tulsa metro area.

Winter (Dec-Jan-Feb) 2009-10

Tulsa: Winter 2009-10 was 5th coldest (34.8°F, since 1905), the 42nd wettest (6.27", since 1888), and the 5th snowiest (17.1", since 1900) winter on record.

Tulsa: This is the first Dec-Jan-Feb period since records began in 1905 that the Tulsa high temperature did NOT reach 65 degrees.

Fort Smith: Winter 2009-10 was the 13th coldest (37.5°F), 18th snowiest (11.0"), and 57th driest (7.49") winter since records began in 1882.

10 events brought measurable snow or ice to the region during Dec-Feb. The two biggest winter weather events in eastern OK and northwest/west central AR were the Christmas Eve 2009 Winter Storm/Near Blizzard (see Dec. reports for details) and the January 28-29, 2010 Winter Storm (see Jan. reports for details). (links provide additional information including detailed summary of the storm, snow/ice accumulation maps, radar imagery, and impacts.)

According to the OCS Mesonet Ticker from Feb. 24, 2010:
"The Mesonet’s instruments that measure solar radiation have received a mere 46.2 percent of possible sunshine this winter [across Oklahoma], the second-lowest total since the Mesonet began in 1994. Only the winter of 1997-98, the second wettest on record [for the entire state] and the “super” El Niño winter, was gloomier."

The active winter weather was likely due to a combination of effects from a moderate to strong El Niño and strongly negative Arctic and North Atlantic Oscillations. The El Niño shifted the active Pacific Jet Stream further south, which led to a storm track over the Southern Plains. Meanwhile, the Arctic and North Atlantic Oscillations were negative (and very strongly negative at times) during the Dec-Feb period. When these oscillations are in the negative phase, colder than average temperatures occur across the U.S., including the Southern Plains.

Outlook

The Climate Prediction Center (CPC) outlook for March 2010 (issued February 28, 2010) indicates an enhanced chance for above median precipitation and an enhanced chance for below average temperatures. For the 3-month period Mar-Apr-May 2010, CPC is forecasting a slightly enhanced chance for below average temperatures and equal chances for above, near, and below median precipitation (outlook issued February 18, 2010).

Sea-surface temperatures in the equatorial Pacific indicate that moderate El Niño conditions currently exist. According to CPC, El Niño is expected to continue, though gradually weaken, through the spring. The one-month and three-month outlooks for the Southern Plains are consistent with the general impacts expected during El Niño events, global climate model output, and long-term trends. An El Niño Advisory remains in effect.

According to the Drought Monitor, no drought conditions exist across eastern OK or northwest AR.