by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
The month of January 2008 was slightly cooler and drier than normal. The month began with above normal temperatures, with readings going below normal at mid-month, and remaining there for most of the remainder of the month. Very windy conditions were present late in the month, as the upper air pattern became progressive with fast-moving storm systems.
Wintry precipitation occurred in parts of the region on the 19th, 25th, and 31st the latter over the extreme north. There were no ice accumulations in the Tyler area. Compared with January 2007, the month was 1.7 deg. Warmer, and 6.71 inches drier.
The thirty-day outlook for January 2008 had called for above normal temperatures and near normal precipitation. The week December 30, 2007-January 5, 2008 saw temperatures about 2 degrees above normal and no rainfall. After a cold start to the new year, temperatures warmed rapidly in the week as upper air high pressure built over the area from the southwest, and Tropical Maritime air replaced the Polar Continental air mass. The week's average temperature was 44.7 deg., which was 2.6 deg. Warmer than the previous week. Compared with the same week in 2007, the week was 2.8 deg. Colder, and 1.34 inches drier.
The week January 6-13 saw temperatures about 9 degrees above normal, and rainfall about 40 percent of normal. The week began very warm under continuing Tropical Maritime air. However, a strong cold front on the 8thwith a reinforcement on the 10th lowered temperatures back closer to seasonal normals. Early in the week, temperatures were running as much as 25 deg. Above normal values. The week's two rains and those were light came with the fronts on the afternoons of the 8th and 12th. Conditions were windy between the 5th and 8th, and again on the 10th and 12th with sharp pressure differences between surface high pressure ridges and cold frontal troughs. The week's average temperature was 55.8 deg., which was 11.1 deg. Warmer than the previous week. Rainfall was 0.34 inch. Compared with the same week in 2007, the week was 3.1 deg. Warmer and 2.24 inches drier.
The week January 13-19 saw temperatures about 4 degrees below normal, and precipitation about 20 percent of normal. Northwesterly winds aloft were present for much of the week, which kept a chill surface air mass in the region. A series of weak disturbances in the upper air flow caused light precipitation during the latter half of the week. The absence of significant Gulf moisture prevented amounts from becoming significant in East Texas, though heavy rains fell along the Texas Coast on the 16th and 18th. Light snow fell in Tyler on the 18th, though there was only a slight accumulation on grassy surfaces. The week's average temperature was 43.2 deg., which was 12.6 deg. Colder than the previous week. Precipitation was 0.11 inch, with a trace of snow. Compared with the same week in 2007, the week was 9.0 deg. Warmer, and 4.35 inches drier.
The week January 20-26 was much colder and slightly wetter than normal. The cold air mass, which entered the region on the 12th, persisted all week, with reinforcing cold fronts on the 22nd and 24th. Weak upper air disturbances crossed during the week, bringing measurable precipitation on five days. The system which crossed on the 25th brought a mixture of rain, sleet, and freezing rain. There was no accumulation of ice. Dense fog formed on the morning of the 26th, lowering visibilities to under 1 mile in Tyler for much of the morning. Skies were overcast for all except 30 of the week's 168 hours, with sun on the 20th and 24th. The week's average temperature was 38.2 deg., which was about 10 degrees colder than normal. Precipitation was 1.11 inches, about 150 percent of normal. Compared with the previous week, the week was 4.8 degrees colder. Compared with the same week in 2007, the week was 7.5 deg. Colder, and 0.71 inch wetter.
The final five days of the month saw dramatic temperature swings, as strong cold fronts on the 29th and 31st ended brief warm-ups. Both fronts were accompanied by showers, and followed by gusty winds. Tyler's peak gusts were 43 mph and 40 mph on the 29th and 31st respectively.
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 2008, RECORDS AND SUMMARY: