The month of November 2001 saw above normal temperatures and near normal precipitation. Compared with November 2000, the month was 8.2 degrees warmer, and 9.55 inches drier. In fact, November 2000 set a record for the wettest November on record. Through November 30, year-to-date rainfall 2.49 inches greater this year than last. Precipitation over the twelve months ending November 30, 2001 is 131.6 percent of normal.
The thirty-day outlook for November 2001 had called for above normal temperatures and near normal precipitation. The week October 28-November 3 saw temperatures two degrees warmer than normal and no rainfall. The week began cool under a modified Polar Continental air mass, but warmed under Tropical Maritime air towards the end of the week.
Upper air high pressure prevent the formation of any rainfall as storm features were shunted away from East Texas. The week's average temperature was 63.4, which was 4.5 degrees cooler than the previous week.
The week November 4-10 saw temperatures about five degrees above normal, and rainfall about five percent of normal. A Polar Maritime air mass moved into the area on the 4th, which lowered temperatures slightly. Another Polar Maritime air mass moved in on the 9th.
This one was overridden by moist air, which caused patchy light rain on the 9th and 10th. The week's average temperature was 63.6 degrees, which was 0.2 degrees warmer than the previous week.
The week November 11-17 saw temperatures six degrees warmer than normal, and rainfall near normal. A Tropical Maritime air mass persisted over the area throughout the week. This was because of upper air high pressure over Central North America. No cold fronts reached the area.
An upper air storm formed over the Southwestern United States on the 13th, and brought significant rains to West and South Texas. Energy ejected from the forming storm on the 12th brought scattered rainfall to East Texas. Amounts varied widely, ranging from a few hundredths of an inch to nearly two inches. Amounts generally increased from northeast to southwest.
Drier air entered the eastern counties on the 16th, which lowered morning low readings into the high 40s on the 17th, while the remainder of the area held in the 50s. The week's average temperature was 63.2, which was 0.4 degrees cooler than the previous week.
The week November 18-24 was three degrees warmer than normal, and rainfall was about 25 percent of normal. The growing season for 2001 ended on the 21st when the temperature fell to or below freezing in most of the area. This year's season was 274 days, with the latest frost of last winter observed on the morning of February 18th. The 2001 season was 274 days, which is 29 days longer than normal. Two migratory storms crossed the region during the week. The storm of the 19th brought only light rainfall, and a mass of modified Polar Continental air. Temperatures recovered rapidly on the 22nd and 23rd ahead of the storm which crossed the night of the 23rd/24th. Gusty winds blew on the 22nd and 23rd ahead of the storm, and on the 24th behind it. A squall line crossed overnight of the 23rd/24th, with amounts mostly under one-third inch.
The week's average temperature was 58.3 deg., which was 4.9 deg. cooler than the previous week. The final partial week saw temperatures fall to well-below normal temperature readings and much above normal precipitation at mid-week as an Arctic air mass moved into the area. This cold air mass was overrun by moist air, which resulted in widespread and heavy rainfall on the 28th as an upper air storm crossed.
The precipitation became a sleet/snow mixture on the 29th. Though there was no ice in the immediate Tyler area, some ice did form on road surfaces over Van Zandt and Henderson Counties. On the morning of the 30th, there were numerous traffic accidents resulting from ice which formed on bridges and overpasses as standing water and moisture in the lower atmosphere froze on these surfaces.
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
November 2001, RECORDS AND SUMMARY: