The month of March 2001 was cooler and much wetter than normal. In fact, it was the wettest March on record. March 2001's 9.92 inches of precipitation eased out March 1945 by 0.03 inch for that honor. March 1922 now slips to third place with 9.82 in., and March 1926 to fourth with 9.40 in. March 2001 was 8.2 degrees cooler than March 2000, and 5.00 inches wetter. Year-to-date rainfall through March 31 is 13.04 inches greater this year than last, and is the greatest year-to-date precipitation measurement through 31 March in the 106 years of government weather records for Tyler. Precipitation during the past twelve months is 154.6 percent of normal. This reflects the wet Spring of 2000, and the very wet 2000- 2001 cool season. The thirty-day outlook for March 2001 had called for above normal temperatures and near normal precipitation; it was not correct.
The week February 25-March 3 saw near normal temperatures and rainfall 380 percent of normal. During the first part of the week, a weak Polar Maritime air mass was over the area. This quickly gave way to a modified Polar Continental air mass, with a storm feature holding nearly stationary off the Pacific Coast. As a result, persistent rain began on the night of the 26th which continued into the 3rd. Rain was particularly heavy on the night of the 27th, when 0.95 inch fell in twenty-five minutes. Moderate to heavy rain fell again on the 1st and 3rd, with light rain on the 28th and 2nd. Considerable fog was present during this period, as well. The temperature held within a range of ten degrees between the evening of the 27th and afternoon of the 3rd, as the cool air mass was trapped beneath a usually low overcast.
The week March 4-10 saw temperatures two degrees below normal and precipitation about 200 percent of normal. Rainfall, falling on the 3rd, was reported on the 4th. This was the last of the rain with the slow-moving storm of the previous week. One significant storm crossed during this week--on the night of the 8th/9th. It brought rains of between one-half inch and two inches to the area. Otherwise, a Polar Maritime air mass was over the area for much of the week, except when moist air returned on the afternoon of the 7th ahead of the next day's storm. Polar Maritime air returned on the 9th and 10th.
The week March 11-17 saw temperatures one degree above normal, and rainfall about 450 percent of normal. Two wet storm systems crossed during the week--one on the 11th-12th, and a second on the 14th. Both storms brought general rains to the area, with the heavier rains occurring on the early-morning of the 12th. Amounts with that storm averaged between one and four inches, while amounts with the mid-week storm varied from half an inch to an inch and a half. Clearing occurred on the 12th-13th, and between the 15th and 17th. Polar Maritime air masses built in behind both storms.
Temperatures during the week March 18-24 ran three degrees cooler than normal, and there was no rainfall. A storm crossed on the 8th-19th, causing cloudiness but no rainfall. Polar Maritime air built in on the 18th-20th, with Tropical air returning on the 22nd. Temperatures began warming on the 20th, with the warming trend continuing into the 23rd. Another storm crossed on the 24th, with rain--which was reported on the 25th. A Polar Continental air mass built in on the afternoon of the 24th.
The week March 25-31, 2001 saw temperatures ten degrees colder than normal and rainfall 150 percent of normal. A mass of Arctic air was trapped near the surface by overrunning moisture. This kept temperatures cold until the 30th. A series of crossing upper air disturbances created rainfall from this overrunning situation. Amounts were rather uniform around the area. With rivers already out-of-banks, these rains continued the flooding. On the 31st, another cold front moved through, bringing drier air into the area.
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
March 2001, RECORDS AND SUMMARY: