The month of May 2006 was warmer and drier than normal, continuing a trend which began in March 2005. For most of the month upper air high pressure dominated the region's weather. This suppressed rain and held up temperatures. Indeed, no rain fell between the 15th and 30th. There was considerably less storm activity during the month than is customary. since the upper air high pushed the storm track well to the north.. Compared with May 2005, the month was 1.9 deg. Warmer, and 0.34 inch wetter.
Year-to-date rainfall through May 31 was 5.11 inches greater in 2006 than in 2005. The thirty-day outlook for May 2006 had called for above normal temperatures and near normal precipitation.
The week April 30-May 6 saw temperatures about 4 degrees warmer than normal, and rainfall about 150 percent of normal. The week began with a dry air mass, with humidities increasing on the 1st as Tropical Maritime air returned.A couple of upper air low pressure features crossed during the week, bringing morning showers on the 4th and 5th, and general and significant rainfall on the 6th. There was little severe weather with these thunderstorms. The week's average temperature was 74.0 degrees, and rainfall was 1.37 inches. This was 4.7 degrees warmer than the previous week. Compared with the same week in 2005, the week was 10.0 degrees warmer, and 1.09 inches wetter.
The week May 7-13 saw temperatures near normal, and rainfall about 15 percent of normal. Upper air high pressure controlled the weather for most of the week, with a weakening on the 10th permitting a weak cold front through the region. The upper air high resulted not only in warm temperatures and high relative humidities, but also in a haze layer on the 9th and 10th. Smoke from fires in Florida and the Yucatan had drifted northward, and was trapped beneath the subsiding air. Rain did not accompany the mid-week cold front because of the warm air layer just above the surface. The week's average temperature was 71.9 degrees, which was 2.1 degrees cooler than the previous week. Rainfall was 0.14 inch. Compared with the same week in 2005, the week was 2.1 degrees cooler, and 0.46 inch drier.
The week May 14-20 saw temperatures about 3 degrees below normal, and rainfall about 75 percent of normal. A modified Polar Continental air mass brought the cool weather of the first half of the week. On the 18th, modified Tropical Continental air began replacing it under upper air high pressure, which warmed temperatures. By the end of the week, Tropical Maritime air was back with higher relative humidities. The week's only rainfall came with passage of the first cold front on the morning of the 14th, with numerous occurrences of severe weather and rainfall of as much as an inch over the southeast and central. The week's average temperature was 71.0 degrees, which was 0.9 cooler than the previous week. Rainfall was 0.70 inch. Compared with the same week in 2005, the week was 4.5 degrees cooler, and there was no rain in 2005.
The week May 21-27 saw temperatures about five degrees warmer than normal and no rainfall. Upper atmospheric high pressure dominated the area's weather during the week. This was responsible for a gradual warming trend in temperatures and the suppression of rainfall. On the 27th, Tropical Maritime air entered the region ahead of the storm system of early in the following week. The week's average temperature was 79.9 deg., which was 8.9 deg. Warmer than the previous week. Compared with the same week in 2005, the week was 1.0 deg. warmer, and 0.92 inch drier.
The final four days of the month were cloudy and showery. Torrential rains fell along the Upper Texas Coast on the 28th and 29th, with only scattered showers over East Texas. A tropical upper air low was over the Middle Texas Coast and was responsible for the area's. weather.
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.
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May 2006, RECORDS AND SUMMARY: