A weak upper-level disturbance will help ignite thunderstorms by the late morning hours across southern portions of the Permian Basin south into the Trans-Pecos area. Some of those scattered thunderstorms could become strong to severe with ‘pocket-change’ size hail. The strongest could produce quarter to ping-pong ball size hail this afternoon.
By the late afternoon, we may see storms grow upscale into a cluster. Should storms grow into a cluster they could begin to move comparatively faster to the east/southeast toward the southern Concho Valley and the southern Hill Country. A localized damaging straight-line wind threat would be possible in addition to some hail.
That cluster would approach the San Antonio metro around midnight. However, it’ll be outrunning upper-level support and moving into a less unstable environment. Thus if storms do make it to Interstate 35 in South-Central Texas this evening they should be weakening. Some storms may remain strong into the early morning hours on Tuesday.
If the storms are able to maintain their organization there is a chance they may make a run at the Middle Texas Coast during the pre-dawn hours Tuesday. At this point, it looks like the cap will ‘squash’ most storms not long after they make it into San Antonio. The threat of severe weather will be comparatively highest west of San Antonio westward towards Pecos and Alpine.
Saturated soil conditions from heavy rains last week will result in elevated amounts of run-off from any rains that fall. Isolated flash flooding is possible, with a particular emphasis on areas that dealt with heavy rain last week.
Scattered storms are expected on Tuesday across South-Central Texas, South Texas, the Rio Grande Valley, and up the coast towards Victoria. A few strong storms with small hail and gusty winds will be possible. However, tomorrow and Wednesday’s storm chances will tend to be diurnally driven and more ‘summer-like’ in their organization. Isolated flash flooding may occur, but widespread flooding is not expected.
After today’s severe weather chances our focus will shift back west for a multi-day severe weather threat. That threat will begin Friday afternoon across the Texas Panhandle, West Texas, and perhaps south into the Permian Basin. We’re way too far out to talk about specific threats, but the setup does seem to favor scattered supercell thunderstorms east of a dryline.
Those storms could grow upscale into a squall line by Friday night. If we do see a squall line fire up it could make its way eastward across a majority of Texas into the morning hours on Saturday. Another round of severe weather is possible Saturday afternoon east of the dryline, which should be 50 to 100 miles farther east compared to Friday.
Sunday *may* be a down day, but the long-range is looking very active. That means the second half of May could be quite busy across the Plains of the United States with severe weather and heavy rainfall chances. It looks like Paige scheduled her ‘chasecation’ perfectly this year.