by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
The month of February 1999 was much warmer and much drier than normal. For most of the month, a west-to-east zonal flow pattern from Northeastern Asia, across the Pacific and North America, and into the Atlantic was present. This kept storm features and cold air masses away from East Texas. Compared with 1998, February 1999 was 5.3 deg. warmer, and 5.51 in. drier. Year-to-date rainfall in 1999 was 7.84 in. less in 1999 than through February 28, 1998. Rainfall over the past twelve months is 47.99 in., about 105 percent of normal.
The only February to be warmer than this past one was in 1976, when the average temperature was 58.5 deg.--0.1 deg. warmer than February 1999. February 1954, with 58.0, slips into third place. February 1999 was the third driest February on record. 1916 is the driest, with 0.16, while 1897 is second with 0.29 inch. The thirty-day outlook had called for above normal temperatures and near normal precipitation.
The first week in February continued the trend of above-normal temperatures established the previous month. Readings averaged 11 degrees above normal in Tyler, with precipitation 0.01 inch. A zonal flow dominated the Continental United States during the week. This kept cold air masses and storm features away from East Texas. Tropical Maritime air was over the region much of the week. The second week in February was about ten degrees warmer than normal, with little rainfall. The pattern of the previous week held.
The third week in February was five degrees warmer than normal, and rainfall was about one-fourth normal. Several weak Pacific cold fronts moved through the region, as a northwesterly flow aloft permitted minor disturbances to cross to the north of the region. The week's rain fell when one of the stronger of these crossed on the 20th.
The final week in February saw temperatures eight degrees above normal and rainfall about 10 percent of normal. Light rain occurred on the morning of the 25th, and a thundershower occurred on the afternoon of the 27th. Upper air high pressure over the Western United States was the dominant feature, blocking storm features and cold air masses from East Texas. The upper air disturbances which did cross were much-weakened by their encounter with the warmer air aloft on their way eastward, and the couple of cold fronts which went through had lost much of their punch.
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
February 1999, RECORDS AND SUMMARY: