by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
December 2005, like the rest of the year, was warm and very dry.
2005 goes into the record books as the second driest and tied for the fifth warmest year in the 110 years of National Weather Service climate records for the Tyler station. 1956, at the nadir of the 1950s drought, still ranks as the driest but not by much. In that year. 24.01 inches of rain fell in the city. Oddly enough, the following year was the wettest on record; in 1957, 67.30 inches of rain fell. There is no reason to believe that that pattern will repeat in 2006. 1925 dropped to the third driest with 27.41 inches. Fourth and fifth driest yearly totals were 28.40 inches in 1963, and 30.03 inches in 1964.
December 2005, with but 0.73 inch, is the sixth driest December on record. The five warmest years in Tyler are: 1921 with 69.6, 1998 with 69.0, 1911 with 68.4, 1939 with 68.1, and 1925 and 2005 with 67.9. The year's highest temperature was 104 degrees on August 22 and 23, while the coldest was 19 degrees on December 9. Of the five warmest years, two have come within the past decade: 1998 and 2005. The growing season was 244 days, between March 17 and November 16; this was normal.
The month of December saw radical temperature swings from very cold at mid-month, sandwiched between very warm at month's beginning and ending. Temperatures ended up being near normal. The month was slightly cooler and drier than December 2004. The temperature difference was -0.6 in 2005, and the rainfall difference was -2.05 inches.
Year-to-date rainfall was 21.27 inches less in 2005 than in 2004. The thirty-day outlook for December 2005 had called for near normal temperatures and near normal precipitation.
The week November 27-December 3 saw temperatures about 2 degrees warmer than normal, and precipitation about 120 percent of normal. The week began and ended unseasonably warm, with all area stations reporting record high temperatures on the 3rd. A storm system, crossing on the 27th/28th, brought the week's rain, and severe weather to parts of the region. Cold fronts on the 28th and 1st lowered temperatures to near seasonal normals for the mid-week period. The week's average temperature was 55.4 deg., which was 0.3 degree cooler than the previous week. Precipitation was 1.22 inches. Compared with the same week in 2004, the week was 7.0 degrees warmer, and 0.31 inch wetter.
The following week--December 4-10--was in sharp contrast. Its average temperature was 11 degrees below normal, and precipitation was about 15 percent of normal. Arctic cold fronts on the 4th and 7th brought very cold temperatures, while a weaker front on the 10th stunted a warming trend. The front of the 7th was accompanied by an upper air storm which brought rain on the evening of the 7th, which became a sleet/freezing rain/freezing drizzle/freezing fog mix overnight. This resulted in a thin ice glaze on bridges and secondary road surfaces on the morning of the 8th. The 8th was the first day since February 25, 2003 when the temperature failed to rise above freezing. Texarkana tied its record low temperature on the morning of the 9th. Warming occurred on the 9th and 10th, though temperatures continued below normal. The week's average temperature was 40.2 degrees, which was 15.2 degrees colder than the previous week. Precipitation was 0.23 inch. Compared with the same week in 2004, the week was 17.0 degrees colder and 0.81 inch drier.
The week December 11-17 saw near normal temperatures and precipitation about 10 percent of normal. Light rain occurred with the cold fronts which crossed on the 14th and 17th. Temperatures warmed ahead of the front of the 14th to slightly above normal levels, and fell to below normal levels after its passage. The week's average temperature was 48.5 deg., and precipitation was 0.12 inch. The week was 8.3 deg. Warmer than the previous week. Compared with the same week in 2004, the week was 2.1 deg. Warmer and 0.26 inch drier.
The week December 18-24 saw temperatures about 2 deg. Cooler than normal, and precipitation about one-third normal. A crossing storm on the 20th-21st brought most of the week's rain, which finally put Tyler above the record dry year of 1956. Arctic air held the region in much below normal temperatures until warming commenced on the 22nd ahead of a weak storm and cold front which crossed on the 24th. This brought some light rain. The week's average temperature was 45.8 deg., and precipitation was 0.38 inch. The week was 2.7 deg. Cooler than the previous week. Compared with the same week in 2004, the week was 4.0 deg. Warmer and 0.88 inch drier.
The week December 25-31 was about 10 degrees warmer than normal, and there was no rainfall. Upper air high pressure built over the area from the west, and a blocking upper air high north of Lake Superior split the jet stream. The result was that the storm track was positioned well to the north of the region. The cold fronts of the 28th and 30th generated no rain, and lowered temperatures only slightly. A record high maximum occurred on the 27th. Gusty winds ahead of each front resulted in numerous grass fires in the region. The wind, combined with very low relative humidities, high temperatures, and dry and dormant vegetation provided optimal conditions for fires to develop. The week's average temperature was 57.8 degrees, which was 12.0 degrees warmer than the previous week. Compared with the same week in 2004, the week was 0.8 degree warmer, and rain did not fall during the week in 2004.
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
DECEMBER 2005, RECORDS AND SUMMARY: