by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
The month of January 2009 saw near normal temperatures and below normal precipitation.
For much of the month, northwest winds aloft blew down the Plains. This transported dry air into the region, and also brought frequent cold fronts. The main thrust of the cold outbreaks for the month was, however, into the Northeastern United States.
The dry air frequently resulted in high daytime temperatures which were 2 degrees above normal for the month and low nighttime readings which were 2 degrees below normal. There were no major winter weather outbreaks. Compared with January 2008, the month was 2.3 deg. Warmer, and 0.42 inch drier.
The thirty-day outlook for January 2009 had called for above normal temperatures and near normal precipitation.
The week December 28, 2008-January 3, 2009 started with near seasonal temperatures, but warmed dramatically on New Years Day when the cold front of the 31st came back northward as a warm front. The week's average temperature of 52.6 was about 6 degrees warmer than normal, and was 4.4 deg. Warmer than the previous week. Compared with the same week in 2007-2008, the week was 7.9 deg. Warmer. The storm system, which crossed early in the following week, brought strong south winds on the 2nd and 3rd, with gusts to near 30 mph. Tyler Pounds Field and Longview Gregg County each reached record high temperatures of 80 and 81 respectively on the afternoon of the 3rd. There was no precipitation during the week, as was the case with the same week one year earlier.
The week January 4-10 saw temperatures about 3 degrees above normal, and rainfall about 150 percent of normal. A cold front and storm system crossed on the 5th, bringing the week's rainfall, and holding temperatures down through mid-week. Late in the week, temperatures warmed ahead of another front which crossed, mostly dry, on the 10th. Conditions were windy on the 9th and 10th. There was only patchy light rain on the morning of the 10th. The week's average temperature was 49.8 deg., and rainfall was 1.34 inches. This was 2.8 deg. Cooler than the previous week. Compared with the same week in 2008, the week was 6.0 deg. Cooler, and 1.00 inch wetter.
An upper air pattern of high pressure to the west and low pressure to the east set up on the 5th, and persisted until around the 21st. This resulted in frequent cold fronts, which contained Polar Continental air. As a result, the week January 11-17 saw temperatures about 5 degrees below normal, and no rainfall. Low temperatures were below freezing on six days during the week, and temperatures did not return to normal until the 17th ahead of another cold front. The week's average temperature was 41.5 deg., which was 8.3 deg. Cooler than the previous. There was no measurable rainfall, though a trace occurred on the morning of the 17th. Compared with the same week in 2008, the week was 1.7 deg. Cooler, and 0.11 inch drier.
The week January 18-24 saw temperatures about 3 degrees above normal, and no rainfall. The air mass was very dry for most of the week. This resulted in cool nighttime temperatures, but very warm afternoon readings towards week's end. Though three cold fronts crossed, limited moisture meant only trace amounts of precipitation. The blocking western upper air high pressure ridge began breaking down on the 21st, which permitted a more progressive weather pattern for the remainder of the month. The week's average temperature was 50.9 deg., which was 9.4 deg. Warmer than the previous week. Compared with the same week in 2008, the week was 12.5 deg. Warmer, and 1.11 inches drier.
The week January 25-31 saw temperatures about 6 degrees below normal, and precipitation about 50 percent of normal. An Arctic cold front, accompanied by an upper air storm, crossed the region on the 26th and 27th. This resulted in some light freezing rain early on the morning of the 27th. A reinforcement of the Arctic air arrived on the afternoon of the 28th, holding temperatures below normal. Warmer air returned on the afternoon of the 31st. After the storm crossed, humidities were quite low. Widespread freezing fog occurred on the morning of the 29th. The week's average temperature was 42.2 deg., which was 8.7 deg. Cooler than the previous week. Precipitation was 0.36 inch. Compared with the same week in 2008, the week was 6.0 deg. Cooler, and 0.20 inch drier.
The reporting period for temperatures and phenomenon on each day is for the twenty-four hours ending at midnight hours GMT--6 p.m. CST and 7 p.m. CDT. The reporting period for precipitation is for the twenty-four hours ending at noon GMT--6 a.m. CST and 7 a.m. CDT. All times are given using the twenty-four hour clock, and are expressed in Greenwich Mean Time.
Observations are from NWS Station 41/9207/4 in Tyler, Texas. The term "normal" refers to averages from the standard climatic period 1971-2000.
MX MN OBS PCPN REMARKS
January 2009, RECORDS AND SUMMARY: