January 2013 Climate and Hydrology Summary

January 2013

Tulsa: January 2013 was the 25th warmest (40.5°F; since 1905) and the 56th wettest (1.54", tied 1923; since 1888) January on record. A trace of snow occurred in January 2013.

Fort Smith: January 2013 was the 20th warmest (43.2°F; since 1883) and the 23rd wettest (3.97", tied with 1890; since 1883). A trace of snow occurred in January 2013.

Fayetteville: January 2013 was the 15th warmest (38.5°F; since 1950) and the 18th wettest (3.03"; since 1950). A trace of snow occurred in January 2013.

McAlester: Daily records set or tied this month include record warm minimum temperatures and a record warm mean temperature.

The record warm minimum temperature of 65°F set on 01/28/2013 tied 01/03/2004 and 01/07/2008 as the warmest minimum January temperature on record in McAlester.

Using the radar-derived estimated observed precipitation from the RFCs, rainfall totals for January 2013 ranged from 1” to around 5”, with the highest totals in east central and southeast Oklahoma as well as west central Arkansas. Due to the heavy rainfall event on January 29, several areas ended the month with 150%-300% of the normal January rainfall, while other areas still only received half of the normal rainfall in January.

It felt more like spring than winter on January 29th, and the spring-like weather brought heavy rain and tornadoes to eastern Oklahoma and northwest Arkansas. Even north central Oklahoma finally received some rain during this event after going 27-78 consecutive days with less than 0.25” of rain (according to the Oklahoma Climatological Survey). Showers and thunderstorms developed along and ahead of a cold front as a strong low pressure system moved into the region. The individual storms moved north northeast as the entire convective line progressed eastward. This led to training thunderstorms and resultant higher rainfall totals. All of eastern Oklahoma and northwest Arkansas received rain from this event, with most of the area recording 0.75”-1.50”. However, several locations had rainfall totals of 2.50” to near 4” of rain. 3 tornadoes also occurred due to the enhanced low-level winds with this system, though thankfully no injuries or deaths were reported. Tornado 1 was an EF-2 that developed in extreme northeastern Sequoyah Co OK and moved rapidly northeast to the north of Natural Dam, AR in Crawford Co. Tornado 2 was an EF-1 and damaged numerous homes along its 4.2 mile path near Elkins in Washington Co. AR. Tornado 3 was also an EF-1 and occurred in the McIlroy Wildlife Management Area near Rockhouse, AR in Madison Co.

According to the Drought Monitor from January 29, 2013, all of eastern OK and northwest AR was in Severe to Exceptional drought. Note that the data cut-off time for the Drought Monitor was 6am on the 29th; therefore, the heavy rainfall that occurred on January 29, 2013 was not included in this Drought Monitor depiction. Exceptional (D4) drought was occurring over portions of Osage, Pawnee, Creek, western Tulsa, Washington, and western Nowata Counties in eastern OK. Severe (D2) drought was present across portions of Ottawa, eastern Craig, and Delaware Counties in eastern OK, and Benton, Carroll, Crawford, and Franklin Counties in northwest AR. Extreme drought (D3) conditions existed across the remainder of the area.

According to the Oklahoma Climatological Survey, January 2013 was the 24th wettest for northeast Oklahoma, the 34th wettest for east central Oklahoma, and the 34th wettest for southeast Oklahoma. Records go back to 1921.

Outlook

The Climate Prediction Center CPC outlook for February 2013 (issued January 31, 2013) indicates an enhanced chance for above normal temperatures and equal chances for above, near, and below median precipitation across all of eastern OK and northwest AR. This outlook is based primarily on short-range computer models. Early-in-the-month models indicate a mid-level ridge over the center of the U.S. and a trough over the southwest.

For the 3-month period Feb-Mar-Apr 2013, CPC is forecasting a slightly enhanced chance for above normal temperatures and an equal chance for above, near, and below median precipitation across all of eastern OK and northwest AR (outlook issued January 17, 2013). This outlook is primarily based on dynamic computer model output, with some input from statistical forecast tools and long-term trends.

According to CPC, ENSO neutral conditions remained through January. ENSO neutral conditions are expected to continue well into Spring 2013, followed by uncertain conditions in the ENSO state beyond that time.