HERE IS THE LATEST FROM THE NATIONAL WEATHER SERVICE:
...Prolonged period of very cold/freezing weather (from Sunday through Wednesday morning)...
...Low chances of light freezing drizzle /sleet (6 pm New Year's Eve through 6 pm New Year's Day Monday)...
...Check the forecast frequently for updates and changes...
Area of Concern:
Very cold weather will cover the entire region, with the coldest temperatures in the Hill Country.
The primary area of concern for frozen precipitation will be the Hill Country and Edwards Plateau Sunday evening, extending this area to include San Antonio and areas southwest to the Rio Grande River late Sunday night through New Year's Day. As of right now the Austin area and northern sections of South Central Texas should remain fairly dry with little to no impacts from frozen precipitation.
Threats & Impacts:
Freezing rain/drizzle/sleet... could accumulate primarily on elevated surfaces such as picnic tables, bridges, overpasses, stairways. The primary threat time will be from 6 pm Sunday (New Year's Eve) through 6 pm Monday (New Year's Day). Widespread travel problems are not expected at this time, but continue to monitor our latest forecasts and updates. Some closed bridges and overpasses are not out of the question.
Prolonged Freezing Temperatures...Temperatures are expected to be below freezing for as many as 60 hours in the Hill Country...more than 24 hours in many other areas of South Central Texas. This prolonged hard freeze will have significant impacts on sensitive plants and pets. Elderly persons or young children could suffer hypothermia if exposed to long duration of extremely cold temperatures. Exposed water pipes and sprinkler system standpipes could break. Take precautions now. The coldest mornings will likely be Tue and Wed mornings.
Wind Chill Temperatures...Wind Chills will drop into the teens most areas on Monday, with some single digit wind chills in the Hill Country as north winds of 15-25 mph combine with these subfreezing temperatures. The winds will start to weaken by Monday night and thus the wind chills will also warm slightly on Tue.
Expected Precipitation Accumulations: Light freezing drizzle will be limited to Trace amounts on New Year's Eve, Freezing rain/sleet should be limited to a few hundredths at most on New Year's Day.
Timing and Overview:
Arctic air is headed our way and will arrive on Sunday. The timing of the event is pretty well set, with the primary threat for light freezing rain from 6 pm Sunday to 6 pm Monday. While some light freezing rain/drizzle is possible, chances are low and if it does occur, it should be very light and confined to areas mainly southwest of a line from Kerrville to San Antonio to Karnes City. The Hill Country may see the freezing temperatures and light freezing drizzle as early as late Sunday afternoon, with the threat pushing south and southwest overnight into Monday. A weak disturbance moving across the southern half of the state may bring some reports of sleet as well on Monday. Accumulations should be minimal. The best messaging is to springboard off the New Year's Day Holiday and urge people to stay inside, warm, and off the roads.
The prolonged freezing temperatures may last for a few days out in the Hill Country (60+ hours). Morning low temperatures may get below freezing every day next week through Friday with teens expected Tue and Wed morning across the Hill Country and north, low to mid 20s elsewhere. Residents should be proactive with their cold weather preparations and do them now. Most areas should warm above freezing on Wednesday. Wind Chill readings will dip well into the Teens, with even lower readings in the Hill Country.
Confidence:
High confidence in the prolonged period of cold weather
Low confidence in where/when the frozen precipitation will fall