April 2010 Summary and Highlights

April 2010

Tulsa: April 2010 was 20th warmest (63.7°F, since 1905) and the 23rd driest (2.08", since 1888) April on record.

Fort Smith: April 2010 was the 20th warmest (64.5°F) and 27th driest (2.25") April since records began in 1882.

2010 is only the 8th time since 1950 in which zero tornadoes occurred before May 1st in the NWS Tulsa CWA (county warning area). The last time this occurred was in 1992.

Eastern Oklahoma and northwest Arkansas only received between 25% and 75% of the normal April rainfall. The exception was far western Osage and far northwestern Pawnee Counties, where above normal rainfall occurred.

According to the Oklahoma Climatological Survey (OCS), southeast OK ranked as the 5th wettest last 365 days (May 2, 2009 - May 1, 2010) since records began in 1921.

According to the Oklahoma Climatological Survey (OCS), east central OK ranked as the 15th driest 30 days from April 2, 2009 - May 1, 2010 since records began in 1921. Southeast OK ranked as 17th driest and northeast OK ranked as 25th driest.

The Climate Prediction Center (CPC) outlook for May 2010 (issued April 30, 2010) indicates a slightly enhanced chance for above median precipitation in west central Arkansas and an equal chance for above, near, or below median precipiation elsewhere. The May 2010 outlook also indicates an equal chance for above, near, and below average temperatures for the entire area. For the 3-month period May-Jun-Jul 2010, CPC is forecasting a slightly enhanced chance for below average temperatures and a slightly enhanced chanec for above median precipitation (outlook issued April 15, 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 weakening through May. The atmospheric response to El Niño has been diminshing since March, and therefore, the outlook has been based more on statistical model output. However, recent above normal soil moisture acros the Southern Plains was an additional factor in the enhanced chances for cooler and wetter conditions. An El Niño Advisory remains in effect.

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