January 2011 Climate and Hydrology Highlights

January 2011

Tulsa: January 2011 was 24th coldest (34.1°F; since 1905), the 23rd driest (0.55"; since 1888), and the 39th snowiest (3.6"; since 1900) January on record.

Tulsa: A record high temperature of 76°F was tied on January 29. The previous record occurred in 1947.

Fort Smith: January 2011 was the 42nd coldest (37.6°F; since 1883), 10th driest (0.51"; since 1883), and the 36th snowiest (2.8"; since 1884) January on record.

McAlester: A record high temperature of 74°F was tied on January 29. The previous record of occurred in 2002.

Fayetteville: A record high temperature of 74°F was set on January 29. The previous record of 73°F occurred in 2002.

Several rounds of snow affected the region during January 2011 (see the detailed report 999kb .pdf). However, the most significant winter storm moved into the area January 31 and brought blizzard conditions and record snow through February 1. A new 24-hour snowfall record of 14" was set in Tulsa, OK, while 10"-15" snowfall totals were common across northeast Oklahoma. Read more about this event here.

Snow fell across all of eastern Oklahoma and northwest Arkansas on January 9-10, though more interestingly, snow was on the ground in 49 states on January 11, 2011. Florida was the only snow-free state that day.

Significantly colder temperatures affected the region following the January 9-10 winter weather event. Most locations across eastern Oklahoma and northwest Arkansas recorded 90-120 consecutive hours (~4-5 days) of below freezing temperatures.

Rainfall totals for January 2011 ranged from around 0.5" to 1.5" across eastern Oklahoma and northwest Arkansas. Most of the region received below normal rainfall this month, with locations along the I-44 corridor receiving near normal rainfall for the month. Portions of southeast Oklahoma and northwest Arkansas only received 10% to 25% of the normal monthly precipitation.

According to the Drought Monitor from February 1, 2011, severe drought (D2) conditions were affecting southern Choctaw County. Abnormally dry (D0) and moderate drought (D1) conditions were affecting the remainder of eastern Oklahoma and northwest Arkansas. This expansion of the drought conditions was due to the below normal precipitation received again this January, which has exacerbated both the long- and short-term rainfall deficits.

According to the Oklahoma Climatological Survey (OCS), northeast OK ranked as the 8th driest January, east central OK ranked as the 7th driest, southeast OK ranked as the 6th driest, and the state as a whole ranked as the 6th driest since records began in 1921. Northeast Oklahoma also ranked as the driest December 1-January 31 period of record.

Outlook

The Climate Prediction Center (CPC) outlook for February 2011 (issued January 31, 2011) indicates a slightly enchanced chance for above average temperatures across eastern Oklahoma and northwest Arkansas. This outlook also indicated a slightly enhanced chance for above median precipitation across western Arkansas, with equal chances for above, near, and below median precipitation across eastern Oklahoma. The enhanced chance for above average temperatures for the 1-month outlook is consistent with La Niña impacts across the southern Plains.

For the 3-month period Feb-Mar-Apr 2011, CPC is forecasting an enhanced chance for above average temperatures and equal chances for above, near, and below median precipitation across eastern Oklahoma and northwest Arkansas (outlook issued January 20, 2011). The enhanced chance for above average temperatures for the 3-month outlook is consistent with La Niña impacts across the southern Plains.

According to CPC, borderline strong La Niña conditions were observed at the end of January. Current computer models indicate that La Niña conditions can still be expected to continue through the remainder of winter 2010-11and into spring 2011. A La Niña Advisory continues, meaning that La Niña conditions are observed and are expected to continue.