Please watch our Daily Weather Video for complete details on the upcoming severe weather threat…

The Storm Prediction Center has placed much of Southeast Texas and South Texas in a standard risk of severe weather for Thursday. A standard risk is defined as a 15 percent chance of experiencing severe weather within 25 miles of any location. Just east of Texas, SPC has issued an elevated risk of severe weather for a large portion of Dixie Alley. Those folks could be dealing with a major severe weather event on Thursday, but we’re not out of the woods in Texas.

Unlike the past few systems that have moved through Texas, moisture will not be an issue. The North American Model (NAM) is showing a large warm sector across the south, with dewpoint values AOA (At Or Above) 60°F with some locations even above 65°. Those numbers are quite impressive for February and are always a warning sign that something nasty could be coming down the track. These projected dewpoint values are more then supportive of organized thunderstorms.

With the rich moisture in place and a strong storm system coming in aloft, instability values will be in excess of 1,500 joules per kilogram (J/Kg). During the winter months, we generally want to see values of at least 500 J/Kg to support the possibility of severe weather. Obviously values over 1,500 J/Kg are more then favorable to support organized severe weather, assuming other factors are in place.

This graphic shows winds at 500 millibars or 18,500 feet above sea level. When looking for the potential of organized thunderstorms, I want to see values at or above 35 to 40 knots. That’s the rough threshold I like to use when determining wind shear aloft. Values should be above 65 knots, so we definietly have enough wind shear to support thunderstorms.

We’re still three days out from this potential event, so a lot can and probably will change. Current data suggests the highest severe weather threat will be east in Louisiana and Mississippi, but there will be enough instability and wind shear in Southeast Texas to support some chance of severe weather. Current data suggests the primary severe weather threats in Texas will be large hail and damaging straight line winds. There may be some tornado threat, but the primary tornado threat will be to our east. We’ll be able to determine the specific hazards once we get a little closer to Thursday. In terms of timing, it looks like it should be a 2 PM to 10 PM deal. We’ll have continuing coverage on this possible event. I’ll try to post an update later tonight once evening model data arrives.