The month of November 2002 was cooler and drier than normal. For the last half of the month, winds aloft were generally out of the northwest, and the southern branch of the jet stream was inactive. This resulted in frequent cold fronts, which came through without precipitation, since the moisture from the Gulf of Mexico was shut off. Compared with November 2001, the month was 5.8 deg. cooler, and 1.39 inch drier. Year-to-date rainfall through November 30 was 39.91 in., which was 12.64 inch less than in 2001. The thirty-day outlook for November 2002 had called for near normal temperatures and above normal precipitation.
The week October 27-November 2 saw temperatures four degrees cooler than normal, and rainfall about two-thirds of normal. The protracted period of cloudiness, which had commenced October 20, continued through the morning of the 29th, with skies clearing at mid-day. Clouds returned at mid-day on the 30th, and were still present through the 2nd. An upper air storm and cold front brought most of the week's rain on the 28th. Moist air overriding the shallow cool air layer brought additional rainfall on the 1st and 2nd, behind a cold front which crossed on the 30th. A cold front also crossed on the 29th. The presence of the cloudiness held temperatures, except for the afternoons of the 29th and 30th, within a narrow range. A persistent upper air trough over Central and Eastern North America was the controlling weather feature during the period. The week's average temperature was 58.8 deg., and rainfall totaled 0.75 inch. The week was 5.8 deg. cooler than the previous week.
Compared with the same week in 2001, the week was 4.8 deg. cooler, and there was no rain during that week in 2001. The week November 3-9 saw temperatures three degrees cooler than normal, and rainfall 160 percent of normal. An upper air storm crossed between the 3rd and 5th, keeping skies cloudy and bringing rain.
A cold front on the 5th lowered temperatures, until Tropical Maritime air returned on the evening of the 8th. The 9th saw windy conditions, and temperatures 13 deg. above normal. The week was 1.2 deg. cooler than the previous week. Precipitation totalled 1.55 in. Compared with 2001, the week was 6.0 deg. cooler and 1.51 in. wetter.
The week November 10-16 saw near normal temperatures and precipitation about one-eighth normal. The week began with Tropical Maritime air in place, which was replaced with Polar Maritime air. Two cold fronts crossed the region--the first on the 10th and the second on the 14th. The week's only rainfall came on the night of the 14th with the second front. Rain was not general, and was confined to the southeastern one-half of the area. Frost was widespread on the 13th. The week's average temperature was 58.3 deg., which was 0.7 deg. warmer than the previous week. Compared with the same week in 2001, the week was 4.9 deg. cooler and 0.84 in. drier The week November 17-23 was three degrees cooler than normal, and there was no rainfall. A northwest flow event set up on the night of the 14th, and continued through the 23rd. This resulted in reinforcing surges of cool air on the 18th, 20th, and 22nd. With little moisture available, there was no rainfall when any of these fronts crossed. Light freezes occurred at favored locations on the morning of the 17th, 20th, and 23rd, though not in Tyler.
A dry air mass resulted in large diurnal variations, with daytime maxima running as much as 35 deg. above nighttime minima. The week's average temperature was 54.0 deg., which was 4.3 deg. cooler than the previous week. In comparison with the same week in 2001, the week was 4.3 deg. cooler, and 0.28 in. drier.
The week November 24-30 was six degrees cooler than normal, and rainfall was about two-thirds of normal. A Polar Continental air mass moved into the area on the 25th, accompanied by a crossing upper air disturbance. As moist air overrode the shallow layer of cold air, rain fell on the 26th. A reinforcing surge of cold air arrived on the 27th, bringing the area's first freeze on the morning of the 28th. Temperatures warmed on the 29th ahead of another cold front, which crossed on the 30th. A northwest flow event set up on the 14th, which was responsible for the continued flow of cool air during most of the last half of the month. The week's average temperature was 47.4 deg., which was 5.6 deg. cooler than the previous week. Compared with the same week in 2001, the week was 1.2 deg. cooler and 1.81 in. 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
November 2002, RECORDS AND SUMMARY: