If it's daytime in mid-April, it means that there's a risk for severe weather somewhere on the Plains. Texas will be ground zero for the storms for the next few days—today, cities like San Antonio, Austin, Dallas, Fort Worth, and Amarillo could all see hail larger than golf balls, damaging winds, and possibly a tornado or two. Insert your favorite "everything's bigger in Texas" joke here.
The Lone Star State is facing three full days of severe thunderstorms before the atmosphere calms down for a little while. Today's threat is ongoing across the Texas Panhandle and from the Dallas/Fort Worth area down through San Antonio. The turbulent weather should shift into southern Texas during the day tomorrow, and storms return with more wind and hail through the heart of the Plains on Saturday.
The Storm Prediction Center has issued an enhanced (three out of five) risk for severe weather across the panhandles of Texas and Oklahoma, where the worst hail, winds, and tornadoes are expected to unfold today. The areas under an enhanced risk are under a tornado watch until 10:00 PM CDT, with a 30% chance of seeing at least two tornadoes, with a low 10% chance of seeing one "significant" (EF-2 or stronger) tornado. In the off-chance that any of you actually live in these very rural areas, you don't need anyone to tell you what to do. You know the drill.
Above are the current severe weather watches in effect as of about 3:30 PM CDT. Counties shaded in blue are under a severe thunderstorm watch, while counties shaded in red are under the aforementioned tornado watch.
The greatest risk to heavily populated areas lies along the corridor from Dallas/Fort Worth down to San Antonio and over towards the coast near Victoria. These areas are under one, big severe thunderstorm watch in effect through 10:00 PM CDT. The greatest risks include damaging winds in excess of 70 MPH and hail larger than golf balls in the strongest storms. A couple of tornadoes aren't out of the question, especially down near the coast—there have been several reports of a tornado touchdown near Refugio, which is halfway between Victoria and Corpus Christi.
We've also seen several reports of quarter-size hail, but some stones up to two inches in diameter are possible. Hail that large will probably give your car a good beating, but please don't stop under an overpass if you're out driving in this mess. The resulting traffic jam isn't worth saving the paint job on your car—it could lead to accidents and delay first responders if they get stuck in the traffic. Try to pull off the road to a parking lot and wait it out.
That being said, folks in this part of the country are well-acquainted with the risk of hail. 20 years ago this May, a "surprise" supercell moved over a festival in Fort Worth known as Mayfest, injuring nearly a hundred people as hailstones up to the size of grapefruits pelted panicked attendees. We shouldn't see anything like this today, but it underscores the threat that hail can pose to people who caught outside without adequate shelter.
There's an enhanced risk for severe weather—a three on a scale from zero to five—across much of southern and central Texas tomorrow, including San Antonio, Austin, Houston, and Corpus Christi.
The risk for severe weather tomorrow is contingent upon how much crud is leftover in the atmosphere from today's mess—if clouds and precipitation stick around too long through the late morning hours tomorrow, it will inhibit instability and lessen the threat for severe weather in many spots. However, models are projecting enough instability and wind shear in the area cities in the risk zone could see the whole run of hazards if strong storms are able to form.
Our friends in the central Plains also face a slight (two out of five) risk for severe weather tomorrow, where the environment will be favorable for the development of supercells. Again, all hazards are possible.
Third verse, same as the first two. The threat narrows out and shifts farther to the east for the first half of the weekend, with a Loch Ness Monster-shaped threat encompassing everyone from Mobile to Houston to Oklahoma City north through central Kansas.
Tens of millions of people could see severe weather over the next couple of days. Make sure you have a way to receive severe weather warnings whether you're at home, at school, or at the office. Keep your cell phone charged and the batteries in your weather radio fresh.