The month of September 2005 was much warmer and somewhat drier than normal. In fact, it replaces September 1910 and September 1998 as the fifth warmest September on record. The four warmer Septembers were all early in the twentieth century: 1911 with 83.6., 1939 with 83.4, 1921 with 83.1, and 1900 with 82.9. The September 1910 and September 1998 monthly average was 81.9, with September 2005 0.1 deg. warmer. Compared with September 2004, the month was 4.3 deg. warmer, and 2.14 inches wetter. Year-to-date rainfall through September 30 is 11.68 inches less in 2005 than in 2004. Much of East Texas remained in extreme drought, though torrential rains from Hurricane Rita on the 24th alleviated some of the moisture deficit across the southeast. The thirty-day outlook for September 2005--which was wrong--had called for near normal temperatures and near normal precipitation. The week August 28-September 3 saw temperatures about 2 deg. warmer than normal, and rainfall about 10 percent of normal.
Catastrophic Hurricane Katrina came ashore in Southeast Louisiana on the morning of the 29th. East Texas was on the fringe of this circulation, which resulted in very warm temperatures until slightly cooler air arrived on the 1st. Three of the rain bands associated with the hurricane crossed on the 29th and 30th, bringing the week's only rainfall. Upper air high pressure, which controlled the area's weather otherwise, slid westward late in the week. This permitted lower nighttime temperatures and comfortable daytime relative humidities. The week's average temperature was 83.1 deg., and precipitation was 0.07 inch. The temperature was 6.1 deg. cooler than the previous week. Compared with the same week in 2004, the week was 6.8 deg. warmer, and rainfall was identical during the comparable weeks in 2004 and 2005.
The week September 4-10 saw near normal temperatures and no rainfall. Upper air high pressure controlled the region's weather through the week. A couple of intrusions of dry air--one on the 4th and a stronger one on the 7th--resulted in cool nighttime temperatures. Daytime high readings in the dry air mass were slightly above normal. The upper air high and the dry air mass suppressed any shower development until the afternoon of the 10th, when a tropical low pressure feature over Southwest Texas brought widely showers to the southwestern counties. The persistent easterly to northeasterly wind and full sun brought haze to the region at mid-week, with daytime visibilities running in the 4-9 mile range. The week's average temperature was 79.9 deg., which was 3.2 deg. lower than the previous week. Compared with the same week in 2004, the week was 3.1 deg. warmer. There had been no rain in 2004, either.
The week September 11-17 saw temperature about 5 deg. warmer than normal, and rainfall about 40 percent of normal. Heat built through the 15th, with a weak cold front that night lowering temperatures over the following two days. The week's only rain fell on the morning of the 16th as an upper air disturbance crossed. A record high minimum temperature was set on the 15th. The week's average temperature was 83.2 deg., and rainfall was 0.28 inch. The week was 3.3 deg. warmer than the previous week. Compared with the same week in 2004, the week was 2.1 deg. warmer, and 0.24 inch wetter.
The week September 18-24 saw temperatures about 8 deg. warmer than normal, and rainfall about 225 percent of normal. For most of the week, a very strong upper air high pressure ridge dominated. The center of the ridge shifted from time to time, accounting for the minor day-to-day temperature variations. The record high maximum temperature was tied on the 18th, 19th, and 21st. A new record high maximum temperature mark was set on the 22nd. On the 24th, Hurricane Rita came ashore near Port Arthur, and moved north-northeastward through the region. This brought rains of up to 10 inches over Shelby County, and held down temperatures on that day. The week's average temperature was 83.6 deg., and precipitation was 1.89 inches. This was 0.4 deg. warmer than the previous week. Compared with the same week in 2004, the week was 7.8 deg. warmer. There was no rainfall during the week in 2004.
Hurricane Rita, which came ashore near Port Arthur on the morning of the 24th as a Category 3 hurricane, caused massive power failures in the Tyler area between the 24th and 27th. There was devastation along the Upper Coast in Port Arthur, and considerable damage to structures, utility grids, and blockage of roads in the southeast. Rita moved rapidly northeastward overnight the 24th/25th, and upper air high pressure built back into the region. Temperatures ran about 10 deg. above normal early in the week until a cold front arrived the night of the 28th. This lower readings significantly on the 29th and 30th. There were scattered showers and thunderstorms with the front, though no rain fell in the city.
The fourteen days between the 15th and 28th saw seven new daily high temperature records set or tied, and a new record for warmest ever for so late in the season.
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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September 2005, RECORDS AND SUMMARY: