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After a couple of quiet weather weeks in Texas things are finally about to heat up or in this case cool down. Confidence continues to increase that we will be impacted by a very cold airmass that’s currently sitting up in Canada. The worst of the cold air looks to impact the Eastern United States but it looks like we’ll also receive our own fair share of the colder air as well. Here’s a look at the projected upper level air pattern next Tuesday from the Global Forecast System. What I really want to point out on this busy-looking graphic are the arrows. The arrows indicate where the jetstream will be blowing which helps forecasters and meteorologists determine where air masses are moving or originating from. In this case that strong jet stream out of the north will be pulling down pure arctic cold air. In fact temperatures across nearly all of Canada and Alaska are below zero this evening. That’s the airmass that will get dislodged by the jetstream and invade the eastern two-thirds of the United States next week.

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So now that we’ve established we have a cold airmass to our north lets talk about when it will arrive here in Texas. Confidence in cold air invading Texas early next week is high. I don’t think there is any question about that at this point. A few questions still unanswered are how cold will the air be when it arrives in Texas and how quickly will the cold front arrive. These arctic cold fronts are notorious for moving faster than weather model guidance indicates. For that reason the model guidance I’m about to show you should be taken lightly considering we’re still several days out from the cold front arriving and that it may end up moving faster than what these graphics indicate.

We’ve used the 18Z afternoon run of the American Global Forecast System (GFS) weather model to create these graphics. We’ll start out late Monday evening with surface temperatures. This run of the GFS has the cold front pushing south quickly into North Texas west into the Concho Valley and Permian Basin. Temperatures across the Texas Panhandle are already below freezing with strong north winds causing wind chill values to fall into the single digits. Notice temperatures south of the cold front are still in the 60s at 12 AM Tuesday across Central, East, and South Texas. Monday looks to be a warm one and we’ll even have to watch for the chance of a few thunderstorms along the Red River during the afternoon hours on Monday.

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Fast forward tweleve hours and we’re now looking at 12 PM on Tuesday. The cold front has continued to quickly push south and now extends from near Eagle Pass to south of Victoria and is getting ready to push out into the Gulf of Mexico from Galveston to Port Author. Temperatures north of the cold front vary from the 40s across Central and East Texas into the 380s across Northeast, North, West-Central Texas into the Permian Basin into the 20s across the Texas Panhandle and South Plains. I want to remind you that these temperatures are not written in stone and are coming directly off the GFS weather model which is just guessing at this point. Down in the Rio Grande Valley where the cold front has yet to arrive temperatures are in the mid 80s by lunchtime Tuesday according to the GFS.

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Right now it looks like Wednesday morning will be the coldest with this arctic air outbreak in Texas. Once again don’t take these temperatures to heart as several factors will determine exactly how low folks go. However the GFS does have extremely cold air in place with temperatures in the 10s from the Texas Panhandle, Northwest Texas, North Texas, Northeast Texas and even parts of East Texas. That kind of cold is definitely enough to cause concern about unprotected piping. Even across the Concho Valley into Central and Southeast Texas the GFS has temperatures falling into the low to mid 20s with freezing temperatures into Deep South Texas. Factors such as cloud cover, wind speed, any snow cover in Texas or to our north will all determine how low temperatures go on Wednesday morning. Regardless it’s going to be cold – its just a question of how cold. The 18Z GFS graphics I showed in this post was actually a little warmer than the 12Z morning guidance.

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Regarding the chance for sleet or snow As of right now it does appear that a few inches of snow will fall across the Texas Panhandle eastward into Oklahoma Monday Night into Tuesday. There is a chance of some winter precipitation across Northwest and North Texas as well on Tuesday but at this time anything that falls is expected to be light. Extreme uncertainty remains regarding any sort of winter weather issues. Factors including but not limited to the evolution of any storm systems, temperature profiles, moisture availability all play critical roles and will make or break any sort of forecast. So at this range all I can say is there is the potential for some winter weather. Exactly where or how much is not something I can accurately answer at this time.

High Confidence
Coldest air of the season will arrive in Texas and the eastern two-thirds of the USA early next week.
We’ll experience temperatures well below average for some of next week.

Moderate Confidence
We believe the cold front will start pushing into Texas on Monday and continue south Monday Night into Tuesday. It may end up being faster/slower.

Low Confidence
There is the potential for winter weather in the form of snow in the Panhandle early next week with some accumulation possible. Because of factors mentioned above confidence is very low regarding any winter weather precipitation forecast across Northwest or North Texas.