||12/04/2009 22:30:00 CST-6
||12/05/2009 08:00:00 CST-6
||0/0 (fatality details below, when available...)
||A deep trough of mid level low pressure, extending from the Upper Midwest southwest into Texas brought a period of cold rain and snow to South Texas on the 4th. When the clouds cleared at the end of an unusually cold afternoon on the 4th, Canadian high pressure overspread the region overnight on the 4th and into the 5th, bringing the coldest surface temperatures in nearly 5 years to all of Deep South Texas.
Morning lows on the 5th dropped to the mid 20s to around 30 in all counties, with freezing or lower temperatures lasting up to 6 hours in typically colder pockets. The freeze was frosty for many critical agricultural areas of the Rio Grande Valley; temperatures hovering just below 32 combined with calm winds limited notable damage to protected crops and plants.
||Daytime temperatures fell into the upper 30s to lower 40s during the afternoon of a chilly, cloudy December 4th, setting the stage for a widespread freeze overnight on the 4th into the morning of the 5th as skies cleared, winds calmed, and temperatures fell steadily from the 30s into the 20s in Brooks County. By daybreak, lows fell to the mid or upper 20s, including 25 at the Falfurrias Cooperative station. Estimated duration of freezing or below temperatures was 7 to 10 hours.