by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
August 2010 was much warmer and drier than normal. In fact, it was the fifth warmest August on record, with an average temperature of 86.7 deg. The warmest August on record was 1951 with 88.0 deg. For an average temperature. Rainfall was about 40 percent of normal. Compared with August 2009, the month was 4.2 deg. Warmer, and 1.40 inches drier.
Year-to-date rainfall through August 31 was 2.12 inches greater in 2010 than in 2009.
For nearly the entire month, upper air high pressure controlled the area's weather. The effects of the heavy June rains on soils and vegetation had worn off, and soil temperatures reached the lower 90s. This meant that nighttime temperatures ran several degrees warmer than normal for most of the month. The thirty-day outlook had called for near normal temperatures and above normal precipitation.
The week August 1-7 saw temperatures about 4 degrees above normal, and no rainfall. An upper air high pressure ridge controlled the area's weather for the entire week. Two tropical lows entered the state during, the week bringing a few afternoon showers. There was, however, no rain in Tyler. The week's average temperature was 87.7 deg., 4.3 deg. Warmer than the previous week. Compared with the same week in 2009, the week was 3.6 deg. Warmer, and 0.33 inch drier.
The week August 8-14 saw temperatures about 5 deg. Above normal, and rainfall about one- fourth normal. Upper air high pressure was in control. Temperatures continued rising as soil temperatures climbed into the lower 90s, and the cooling effects of June's heavy rainfall disappeared. A weak surface boundary caused isolated showers on the afternoon of the 12th, which brought the week's rainfall. The week's average temperature was 88.6 deg., which was 0.9 deg. Warmer than the previous week. Rainfall was 0.16 inch. Compared with the same week in 2009, the week was 5.3 deg. Warmer, and there was no rainfall in 2009.
The week August 15-21 saw temperatures about 5 deg. Above normal, and rainfall about one- third normal. The upper air ridge was present for virtually the entire week. Widely scattered afternoon showers developed on most days, due mainly to daytime heating and the moist atmosphere. Best coverage was on the 18th and 19th. Tyler's average temperature during the week was 87.9 deg., which was 0.7 deg. Cooler than the previous week. Rainfall was 0.20 inch. Compared with the same week in 2009, the week was 4.5 deg. Warmer, and there was no rainfall in 2009.
The week August 22-28 was slightly cooler, with temperatures about 2 deg. Above normal and no rainfall. After starting out with the highest temperatures of the Summer, a cold front brought lower readings and comfortable relative humidities on the 25th, which persisted through the end of the week. >From the 25th through the 28th, temperatures were a few degrees below normal. A dry air column or no available lifting energy prevented the formation of any rainfall. The week's average temperature was 83.9 deg., 4.0 deg. Cooler than the previous week. Compared with the same week in 2009, the week was 2.8 deg. Warmer, and 0.38 inch drier.
Slightly above normal temperatures and humid air returned for the final three days of the month. Widely scattered understorms developed each afternoon, with rain falling in Tyler on the 30th. A weakness in the upper air high pressure ridge combined with the ample moisture and daytime heating to produce the showers.
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
AUGUST 2010, RECORDS AND SUMMARY: