By Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
The month of April 2006 was much warmer and drier than normal. It was, in fact, the third warmest April on record with an average temperature of 71.9 degrees. April 1925 and April 1930 were each about 5 degrees warmer than April 2006. April 1896 drops to fourth warmest with an average temperature of 71.5. No rain fell during the first half of the month, with near normal rainfall during the last half. Compared with April 2005, the month was 6.4 deg. Warmer and 0.72 inch wetter. Year-to-date rainfall through month's end was 4.76 inches greater in 2006 than in 2005. The thirty-day outlook for April 2006 had called for above normal temperatures and near normal precipitation.
The week March 26-April 1 saw temperatures about 2 degrees warmer than normal, and rainfall about 60 percent of normal. A cool high pressure ridge dominated the area's weather early in the week, with a crossing storm system at mid-week. This brought the week's rainfall. The storm was followed by the establishment of upper air high pressure from North Mexico, which increased temperatures. Surface low pressure to the west brought in humid air after the 30th. The week's average temperature was 64.0 degrees, which was 15.1 degrees warmer than the previous week. Rainfall was 0.49 inch. Compared with the same week in 2005, the week was 3.9 degrees warmer and 0.72 inch drier.
The week April 2-8 saw temperatures about 7 degrees warmer than normal, and no rainfall. The upper air high pressure ridge persisted, breaking down long enough at week's end to permit a cold front through the region. Temperatures were above normal through the 7th, with cooling to slightly below normal between the 8th and 10th. Dry air in the middle atmosphere along with the influence of the ridge prevented any rain from forming with the passage of the front. the week's average temperature was 72.0 degrees, which was 8.0 degrees warmer than the previous week. Compared with the same week in 2005, the week was 7.0 degrees warmer and 0.23 inch drier.
The week April 9-15 saw temperatures about 4 degrees warmer than normal, and no rainfall. A cool air mass gave way early in the week to Tropical Maritime air, which raised temperatures and humidities beginning on the 11th. Upper air high pressure steered storm systems well to the north, keeping the region dry. The week's average temperature was 69.7, which was 2.3 degrees cooler than the previous week. Compared with the same week in 2005, the week was 5.4 degrees warmer, and 0.05 inch drier.
The week April 16-22 continued the warm trend, with temperatures running about 10 degrees above normal, and rainfall near normal. Record temperatures occurred at area stations on the 17th, 18th, and 19th, with Tyler setting a record on the 17th. Strong upper air high pressure was the dominant weather feature until a cold front and storm system arrived on the 20th. This lowered temperatures and brought the week's rainfall. Amounts of more than two inches were common north of the IH-30 Corridor, and south of a Terrell-Center line. Severe weather occurred on the night of the 19th, and early on the morning of the 21st.
A cool high pressure ridge followed the front, bringing a pleasant end to the week. The week's average temperature was 76.5 deg., which was 6.8 degrees warmer than the previous week. Rainfall was 0.73 inch in Tyler. Compared with the same week in 2005, the week was 7.3 degrees warmer, and there was no rain in 2005.
The week April 23-29 saw near normal temperatures and near normal rainfall. Cold fronts crossed on the 25th and 29th, each of which resulted in rain and lower temperatures. Rainfall with both fronts was significant in parts of the area. With the first one, amounts were heaviest along and north of IH-30; the second brought rains of as much as five inches to the East Texas Lakes Country. Both systems resulted in a few reports of severe weather on the night of the 25th and morning of the 29th. The week's average temperature was 69.3 deg., 7.2 deg. Cooler than the previous week. Rainfall was 0.96 inch. Compared with the same week in 2005, the week was 2.3 deg. Warmer and 0.70 inch wetter. The 30th was sunny and mild.
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
APRIL 2006, RECORDS AND SUMMARY: