For the northern half of the state, a cluster of showers and storms expected to continue moving east from the south plains into the rolling plains for the next several hours. Rainfall is expected to be light for the most part, but a few of the stronger cells at the southern end of this cluster of storms could drop a half inch of rain along with small hail and frequent lightning. Across north Texas, scattered light showers are expected overnight. No severe weather is expected, but don’t be surprised to hear a few rumbles of thunder.
For southwest, south central and south Texas, isolated severe thunderstorms are expected to continue into early tomorrow morning. The storms this afternoon have been slow movers dropping multiple inches of rainfall along with producing very large hail and damaging wind gusts along their paths this afternoon and evening. If any lull in activity is realized overnight, it will be brief as additional storms are expected to form and merge into a larger convective system which is expected to track east/southeast across south central and south Texas by early tomorrow morning. Damaging winds, large hail and frequent lightning will be the main threats along with the potential for flash flooding over areas where these storms eventually track during the overnight hours. The previous Severe Thunderstorm Watch expected to end at 10pm has been extended further east into the San Antonio area through 1am tomorrow. The counties added are Atascosa, Bexar, Blanco, Comal, Gillespie and Kendall. Here’s a look at the latest HRRR short-range simulated forecast model output for how things may look overnight into early tomorrow morning.
For tomorrow, the cold front will drop down into south Texas by early tomorrow, and as an upper low over the desert southwest draws closer, we’ll likely see additional chances for strong to severe storms once again across southwest Texas. Confidence is somewhat low in how things will evolve tomorrow morning as most of the short-range forecast models are not consistent with development tomorrow. Nevertheless, we’re expecting to see conditions similar to today with strong to severe storms developing along or near the stalled frontal boundary from the Big Bend region into the Rio Grande plains of southwest Texas. Storms should develop into supercells initially near the TX/Mexico border, moving east with the potential to congeal into a convective system that moves into south central Texas by tomorrow evening. Large hail, damaging winds and a few tornadoes will be the main threats tomorrow afternoon. If a convective system does develop over south central Texas tomorrow evening, then damaging winds and hail would become the main threat. Flooding will also be an issue, especially for storms moving over areas that have already seen recent rainfall. The Storm Prediction Center has addressed this potential with a Slight Risk (Category 2 Risk) across southwest Texas for tomorrow, but once this evening’s model data has been analyzed, we may some adjustments by tomorrow morning.