October’s Weather Warm and Dry, Could Continue Through Rest of 2010

October’s Weather Warm and Dry, Could Continue Through Rest of 2010
Gary McManus
Associate State Climatologist
Oklahoma Climatological Survey

Dry and warm conditions continued over much of the state, although a late-month drink gave a bit of relief to drought-plagued southwestern Oklahoma. A powerful upper-level storm that brought significant rains to the southwestern quarter of the state kept this October from finishing as one of the state’s top-ten driest on record. Despite that moisture, however, much of the state still received a meager 20-60 percent of normal rainfall for the month. According to data from the Oklahoma Mesonet, October ranked as the 30th driest since records began in 1895 with a statewide average of 1.74 inches, 1.64 inches below normal. Temperatures finished above normal for the third consecutive month as well with a statewide average of 62 degrees, 0.7 degrees above normal, to rank the month as the 51st warmest on record.  In a bit of a change from recent warm months, high temperatures led the way at 2.6 degrees above normal while low temperatures were 1.4 degrees below normal.

Only southwest Oklahoma saw a significant moisture surplus with 3-5 inches of rain. Northeastern Oklahoma was particularly dry with an average total of 1.04 inches, more than 2 inches below normal and the 14th driest on record for that area. The Oklahoma Mesonet site at Medicine Park led the state with 4.57 inches. That stands in stark contrast to Boise City where little more than a quarter of an inch fell. Of the Mesonet’s 120 stations, 21 saw less than an inch of rainfall during the month while 79 had less than 2 inches.

Temperatures were 3-4 degrees above normal in parts of the northwest to 1-2 degrees below normal in the southeast. The average temperature for west central Oklahoma was 2.4 degrees above normal to rank as the 23rd warmest October on record. Southeastern Oklahoma, on the other hand, fell 0.5 degrees below normal to rank as the 40th coolest. Not surprisingly, Kenton was the coolest locale in the state with an average temperature of 56.8 degrees. Medicine Park was not only the wettest site but also the warmest as well with an average temperature of 65.4 degrees. The highest recorded temperature during the month was 92 degrees at Buffalo on the seventh. Kenton came in with the lowest temperature of 20 degrees on the 28th. Freezing temperatures were recorded at 64 Oklahoma Mesonet stations during October.

Barring a cool or wet final two months, the year is on pace to finish warmer- and drier-than-normal. Through October, the 2010 statewide average temperature was 63.2 degrees, 0.3 degrees above normal and the 39th warmest such period on record. On the precipitation side, the statewide average was 2.61 inches below normal at 29.24 inches. That ranks this January-October period as the 53rd driest on record.

The National Weather Service’s Climate Prediction Center holds little hope for a cool or wet finish to the year. Long-range outlooks for both November and November-January indicate an increased chance for above normal temperatures and below normal precipitation. Those outlooks are influenced by a moderate-to-strong La Niña that developed in the waters of the equatorial Pacific during the summer. During La Nina events, Oklahoma and the southern United States exhibit an increased tendency for warmer and drier winters.