The month of October 2015 was much warmer and very much wetter than normal. In fact, October 2015 becomes the third wettest October on record, behind October 1985 with 14.82 inches, and October 2009 with 13.62 inches. This stands in sharp contrast to July 2015 tying for the driest July on record, and September 2015 the fifth driest September.
The very dry pattern which set up in mid-June broke dramatically in mid-October. October 2015 was not dissimilar from October 2014: October 2015 was 0.1 deg. Warmer, and 4.20 inches wetter than the wet month of October 2014. Year-to-date rainfall is much greater in 2015 than in 2014: 17.01 inches wetter this year than last. The thirty-day outlook had called for near normal temperatures and near normal precipitation. When revised at the end of September, it called for near normal temperatures and above normal precipitation.
The month began with cool temperatures between the 1st and 4th. This was followed by warming, which persisted through the 15th. Weak cold fronts on the 9th and 12th lowered overnight temperatures, but daytime readings continued running above normal.
Aside from a few isolated showers on the evening of the 12th, the first half of the month was dry. An upper air high ridge oscillated back and forth during this period, and was the major factor responsible for the warm temperatures. In addition, low humidities, dry vegetation, and clear skies were also factors. Tyler (both city and airport), Longview, Shreveport, Texarkana, Dallas-Fort Worth, Waco, and Austin all set or tied record high readings on the 15th. A cold front arrived on the morning of the 16th. This brought the very warm readings to an end.
Temperatures warmed to 5-8 degrees above normal between the 18th and 22nd. Then, came an enormous rain event from the 23rd through the 25th. The combination of a good moisture tap from the Gulf of Mexico at lower levels, a strong tap from Hurricane Patricia at upper levels, two upper air lows, and a slow-moving cold front brought torrential rains to roughly the western half of the area. West of a Texarkana-Tyler-Palestine line, between five and twenty inches of rain fell, with the heaviest over parts of Henderson and Navarro Counties. East of this line, amounts were much lighter, with around four inches along the Louisiana border.
Tyler observed two daily rainfall records on the 23rd and 24th, and had its fourth highest twenty-four rainfall total on record of 7.66 inches ending at 7 a.m. on the 24th. Gusty north to northwest winds occurred on the night of the 25th and morning of the 26th. This was due to a deep surface low pressure area over Louisiana the remnant circulation of what was once Hurricane Patricia. Mild and dry weather was present from the 26th through the 29th. A weak cold front on the 28th lowered temperatures slightly from the slightly above normal readings since the 27th. Another storm system crossed between the 30th and November 1. This brought rain of between one and five inches to the area. A cold front on the 31st ended the heavier rainfall, thought lighter amounts continued into the evening of November 1.
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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October 2015, RECORDS AND SUMMARY: