The next three days are going to be active in the weather department. Tuesday night into Wednesday is going to be particularly active with a crazy strong area of low pressure developing of the Southern Plains. As that area of low pressure rapidly deepens (intensifies) Tuesday night we’re going to see low-level winds ahead of a Pacific cool front become extremely strong. Combined with a probable squall line that will be moving east we could see the stage set for damaging winds, small hail, and brief/spin-up tornadoes. There are a few factors that could make the severe weather threat marginal or could greatly enhance the risk. We’ll discuss all of that in detail below.
An upper-level low is located off the coast of California this morning. Over the next 18 to 24 hours it’ll slowly drift south before beginning to move to the east/northeast. On Tuesday that upper-level storm system will slowly be moving east across Arizona and New Mexico. That’ll place Texas in a favorable corridor for lift – and chances for showers and thunderstorms. By Tuesday night the upper-level storm system will intensify in conjunction with a surface low in southwestern Kansas.
Nearly every weather model is in agreement that a very strong surface low pressure will take shape beginning Tuesday night in eastern Colorado. That surface low will deepen over 20 millibars in the time-frame of 12-15 hours. The result will be extremely strong wind fields aloft in Texas and Oklahoma along and ahead of a surface cool front Tuesday night into Wednesday morning.
Southerly winds at about 5,000 feet above the surface (known as the low-level jet) will be between 80 and 95 MPH. Winds at one to two thousand feet above the surface will be at 70 to 80 MPH. We’re also going to have to deal with a non-thunderstorm high wind event behind a dryline/Pacific cool front on Wednesday.
There will be off and on rain chances today across parts of the state. Your favorite weather app can undoubtedly give you more local information on those. We’re not expecting severe weather, although I can’t rule out some small hail with any stronger storms.
Tonight’s severe weather outlook
We have a level one risk of severe weather tonight for the Borderland, Far West Texas, and the Davis Mountains. This includes El Paso, Fabens, Sierra Blanca, Van Horn, Presidio, Alpine, and Panther Junction. This marginal risk of severe weather has been issued due to the potential for borderline severe hail in stronger storms overnight. Most storms will remain sub-severe, but some storms may briefly approach severe limits with quarter size hail. Locally heavy rain and dangerous cloud to ground lightning are also expected with most thunderstorms.
Severe weather chances increase Tuesday afternoon/evening through Wednesday morning
As we transition into Tuesday afternoon through Wednesday morning we’ll see a higher probability of strong to severe thunderstorms involving a Pacific cool front and an eastward moving line of thunderstorms.
A level two risk of severe weather is in place for the Permian Basin, West Texas, the Big Country, Concho Valley, Edwards Plateau, Hill Country, and western portions of Central and North Texas. A level one risk of severe weather includes the Borderland, Far West Texas, the Davis Mountains, the Texas Panhandle, Texoma, North Texas, and Central Texas.
The risk zone will generally begin experiencing a threat in the west late Tuesday afternoon and will move eastward to the eastern risk zone delineations by 4-6AM Wednesday.
A level one risk of severe weather will continue into the late morning hours on Wednesday for Northeast Texas, East Texas, Southeast Texas, the Coastal Plains, and the Brazos Valley. Think of that as a continuation of the risk from Tuesday night.
So in reality, we have a severe weather risk all the way from El Paso to Beaumont over a 24 hour period. I sense caffeine in the future.
Large hail and localized damaging wind gusts will be possible with initial storm development in far West Texas on Tuesday. Storms should quickly grow into a squall line that will move east across the aforementioned regions Tuesday night and into the morning hours on Wednesday. Localized damaging wind gusts and spotty hail will be possible with the squall line. I cannot rule out brief/weak tornadoes given the extreme amount of wind shear in place, but this setup isn’t optimal for squall line embedded tornadoes.
One thing we won’t have a lack of is wind shear. As that surface low gets cranking Tuesday night we’ll see wind shear values in the extreme category. That’s not unusual for ‘cool season’ systems, although we don’t usually have instability to work with (hence no severe weather). In this case, we’re going to probably have modest amounts of instability along and just ahead of that squall line across the western half of Texas. Instability values will be higher the farther south you’re located and lower with northern extent.
My main concern with the damaging wind potential is that these strong-forced squall lines tend to bring some of those higher winds aloft down to the surface. Given the expectation of 80-95 MPH winds a few thousand feet above the surface Tuesday night into Wednesday morning, one might understand my concern for 50-70 MPH winds reaching the surface.
Are damaging winds guaranteed and does it mean everyone is going to get blown halfway to Shreveport? Goodness gracious no! Instability values are going to be marginal and will play a significant role in the eventual severe weather threat.
If instability values trend up so would the threat of more widespread damaging winds and hail. Likewise, if we end up with little to no instability, those stronger winds would have a tougher time reaching the surface. We’re still going to have a squall line tomorrow night into Wednesday morning, even if it’s just a thin line of showers.
Just understand that while tomorrow night’s setup isn’t a perfect setup for a big wind event, I’m still concerned we may have instances of damaging straight-line winds, spotty hail (mostly dime to quarters), and even a low-end threat for brief tornadoes. If instability values end up even just a little higher we could be dealing with a more widespread threat.
The squall line should weaken as it approaches and moves east of Interstate 35 a few hours before sunrise on Wednesday, although it may continue into Arkansas and Lousiana as a thin band of showers by Wednesday afternoon.
Very strong winds expected on Wednesday as the sun comes out
Precipitation will quickly come to an end from west to east across the western two-thirds of Texas by Wednesday afternoon as the Pacific cool front moves east. Clearing skies and warming temperatures behind that front, along with continued very strong winds aloft, will allow for some of those higher winds to translate down to the surface.
We’re anticipating wind gusts exceeding 90-100+ MPH in the Guadalupe Mountains in far West Texas. Wind gusts of 60 to 70 MPH are possible across the Texas Panhandle, West Texas, into the Permian Basin, and Trans-Pecos. Winds of 50 to 55 MPH are possible across Northwest Texas, West Texas, into the Concho Valley. Depending on how quickly clouds clear out along I-35 we may see winds approaching 45 MPH in Texoma and North Texas.