by Robert K. Peters, Ph.D. - National Weather Service Cooperating Observer
The year 2006 joins 1939 as the fourth warmest year in National Weather Service Records for the Tyler station. The year's average temperature was 68.1 deg., which was 1.6 deg. Warmer than normal. Of the five warmest years, three have come within the past nine years: 1998 with 69.0 second warmest), and 2005 with 67.9 (fifth warmest.) Tyler National Weather Service records date to 1896. Tyler is but one of several stations and meteorological services worldwide reporting record warmth. This is further evidence of global warming. The British Meteorological Service reported 2006 as the warmest year on record; records of the "Met" date to 1657.
December 2006 was warmer and wetter than normal. The month began quite cold, but warmed at mid-month, with return to seasonal temperatures late in the month. December 2006 was 1.9 deg. Warmer than 2005, and 4.71 inches wetter. Yearly rainfall was 14.06 inches greater in 2006 than in 2005. The severe drought conditions began a slow improvement late in the year the two-year rainfall deficit was 30.7 percent as of December 31, with 2005 having been the second driest year on record in Tyler. The two-year rainfall deficit at the end of 2005 was 22.7 percent, since 2004 had experienced slightly above normal precipitation.
January 2006 was the fifth warmest January, and April the third warmest April. In addition, August was nearly 4 degrees warmer than normal but not a record. The year's warmest temperature was 103 on August 16, while the coldest reading was 23 on December 8. The warm season was 26 days longer than normal at 173 days; while the growing season was four days shorter than normal at 241 days.
The 2006 tropical storm season saw only 9 named tropical cyclones, compared with 28 in 2005.
The thirty-day outlook for December 2006 had called for near normal temperatures and above normal precipitation. The week November 26-December 2 saw temperatures slightly above normal, and near normal precipitation. The week began very warm, and ended cold. A Tropical Maritime air mass over the area during the first half of the week was replaced by Polar Continental air, behind a sharp cold front on the 29th. The week's rain fell with a crossing disturbance ahead of the front on the 28th. The week's average temperature was 54.3 deg., and rainfall was 1.05 inches. This was 0.1 deg. Cooler than the previous week. Compared with the same week in 2005, the week was 1.1 deg. Cooler, and 0.17 inch drier.
The week December 3-9 was 10 degrees colder than normal, and there was no precipitation. Polar Continental air covered the area during almost the entire week. Each morning during the week except for two saw below freezing temperatures, with readings in the 20s on four mornings. The very dry air mass meant that precipitation did not accompany the cold fronts of either the 3rd or 7th. A short-lived warm-up on the 6th preceded the latter front. Blustery winds on the 3rd and 7th resulted in low wind chill equivalent values. Upper air high pressure to the west of the region meant that cold air was brought southward during the week. The week's average temperature was 41.2 deg., 13.1 deg. Colder than the previous week. Compared with the same week in 2005, the week was 1.0 deg. Warmer, and 0.23 inch drier.
The week December 10-16 saw temperatures about 8 degrees warmer than normal, and near normal rainfall. The Polar Continental air mass was replaced early in the week by a weak Polar Maritime air mass, and late in the week by a strong Tropical Maritime air mass. The result was a warming trend in temperatures, which brought readings of 20 degrees above normal by week's end. As the Tropical Maritime air flowed over the cooler ground on the morning of the 15th, dense fog covered the entire area. Lighter fog was present on the morning of the 16th, along with gusty winds during the afternoon. A crossing storm system on the 10th-11th ahead of the Pacific cold front brought the week's rain. Dense fog was also widespread on the mornings of the 11th and 12th, and was associated with rain from the crossing storm. The week's average temperature was 57.9 deg., which was 16.7 deg. Warmer than the previous week. Rainfall was 0.75 inch. Compared with the same week in 2005, the week was 9.4 deg. Warmer, and 0.63 inch wetter.
The week December 17-23 saw temperatures about 10 degrees warmer than normal, and rainfall about 40 percent of normal. Record high temperatures began the week as the Tropical Maritime air mass persisted under upper air high pressure. At mid-week, the pattern changed, with cold fronts on the 19th and 21st, and a crossing upper air storm which brought the week's rains on the 19th and 20th. By late-week, temperatures were back down to seasonal normals. The week's average temperature was 57.9 deg., identical with the previous week. Precipitation was 0.44 inch. Compared with the same week in 2005, the week was 12.1 deg. Warmer, and 0.06 inch wetter.
The week December 24-30 saw temperatures about 3 degrees warmer than normal, and rainfall about 400 percent of normal. The week began and ended with strong storm systems. General rains of two to four inches fell on the 24th and 25th. On the 29th and 30th, general rains of one to eight inches fell. A weak Polar Maritime air mass moved into the area on the 25th, and gave way to rapidly returning Tropical Maritime air on the 28th. At least three tornadoes occurred on the afternoon of the 29th: in Leon County, in Henderson and Anderson Counties, and a third in Henderson County. The week's average temperature was 50.0 deg., and rainfall was 4.25 inches. This was 7.9 deg. Cooler than the previous week. Compared with the same week in 2005, the week was 7.8 deg. Cooler. There was no rain during the week in 2005.
The month ended with cool and dry weather as Polar Maritime air built in behind the departing storm of the 29th-30th.
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 2006, RECORDS AND SUMMARY: