by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
The month of August 2004 was cooler and wetter than normal. For much of the month, upper air high pressure was situated to the west of the region, and low pressure to the east. This permitted cold fronts to drop into the region at about one-week intervals. Compared with August 2003, the month was 2.9 deg. cooler and 2.71 inches wetter. Year-to-date rainfall through August 31 was 0.67 inches more in 2004 than last year.
The last cool August was in 1992, when the average temperature was 78.4 deg. The record cool August was in 1971, with a 78.1-deg. average. The normal August average temperature is 83.3 deg. The last time August was as wet as was that in 2004 was in 1998--when rainfall was 4.71 inches. The 1998 Summer was also one of the hottest on record. The average Summer temperature for 2004 was 79.9 deg., which is 2.3 deg. cooler than normal. Summer rainfall was 13.24 inches. This was 157.2 percent of normal. This was less than that in Summer 2003, which was skewed by record rainfall of 14.08 inches. July and August 2003 were dry, with a total Summer rainfall of 16.80 inches. Meteorological Summer is the months of June, July, and August- -different from astronomical Summer which runs from about June 21 to about September 21.
The Summer of 2004, though cool, was not a record cool Summer. The average temperature for the Summer of 2003 was 80.1 deg., 0.2 deg. warmer than Summer 2004. The highest temperature in Summer 2004 was 98, which occurred four times. The highest for Summer 2003 was 102, occurring on August 6. There were no days above 100 deg. in either 2001 or 2002. Use of energy for cooling should run low in Summer 2004, with cooling degree-days about 10 percent below normal for 2004. The thirty-day outlook for August 2004 had called for below normal temperatures and near normal precipitation. When revised on July 31, it was changed to forecast below normal temperatures and above normal precipitation.
The week August 1-7 saw temperatures near normal, and rainfall about one-half normal. In fact, it was the warmest week of the Summer season. Upper air high pressure controlled the region's weather between the 1st and 5th, bringing above normal temperatures for early- and mid-week. On the afternoon of the 5th, a cold front crossed, which lowered readings through the end of the week. Temperatures warmed through mid-week, as the upper air high built back into the area. The week's average temperature was 83.3 deg., and rainfall was 0.42 inch. This was 4.6 deg. warmer than the previous week. Compared with the same week in 2003, the week was 1.7 deg. cooler. There was no rainfall during that week last year.
The week August 8-14 saw temperatures about 6 deg. cooler than normal, and rainfall about 125 percent of normal. A disturbance, crossing on the 9th, caused scattered showers and thunderstorms. These brought isolated heavy downpours. On the afternoon of the 11th, a strong cold front and accompanying upper air low crossed. This also brought showers and thunderstorms, and sharply cooler readings through the end of the week.The week's average temperature was 76.9 deg. and rainfall was 0.99 inch. This was 6.4 deg. cooler than the previous week. Compared with the same week in 2003, the week was 2.6 deg. cooler, and 0.06 inch drier.
The week August 15-21 was about 6 deg. cooler than normal, with rainfall about 400 percent of normal. The week began cool, but warmth and moisture returned at mid- week ahead of another storm system and cold front. his produced a significant rain event between the 19th and 23rd, which brought between one and seven inches of rain to the region. Clouds and rain cooled temperatures after the 19th. The week's average temperature was 77.3 deg., which was 0.4 deg. warmer than the previous week. Rainfall was 2.69 inches. Compared with the same week in 2003, the week was 7.3 deg. cooler and 2.47 inches wetter.
The week August 22-28 saw near normal temperatures and rainfall about 75 percent of normal. After rain ended on the 23rd, warm and very moist air returned on the 24th. This brought high nighttime temperatures between the 25th and 28th, with daytime readings holding near normal. Upper air high pressure, extending northward into the region from the Gulf of Mexico, kept conditions dry until another storm system and cold front arrived on the 28th. The week's average temperature was 81.9 deg., which was 4.6 deg. warmer than the previous week. Rainfall was 0.45 inch. Compared with the same week in 2003, the week was 1.5 deg. cooler and 0.19 inch drier.
The final three days of the month saw below normal temperatures as high pressure built in behind the front. A shower on the morning of the 28th brought the only rain reported for the period.
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 2004, RECORDS AND SUMMARY: