An upper-atmospheric low pressure system is approaching Central and South Texas from the north. As the weather disturbance interacts with an extremely moist atmosphere over the next 24 hours, several slow moving and intense thunderstorms are likely to develop across the region.
The biggest concern will be flooding, because the storms that do form are likely to be quite slow-moving, capable of dropping several inches in a relatively short period. The San Antonio area will have a few chances of storms throughout the day, with the highest chances in the afternoon and evening. A flood watch is in effect for the region until at least 7 p.m. today, but it could be extended later into the night.
Sunday storm timeline
Morning (4 to 10 a.m.): A cluster of overnight storms is expected to continue during the morning hours Sunday across the Texas Hill Country. The best chance of early morning storms will occur north of San Antonio, in cities like Kerrville, Comfort, Fredericksburg, Boerne, Blanco, Canyon Lake, Blanco and Burnet.
Overall rain chances will be quite high in the Hill Country, at 50 to 70%. A major flash flood threat is also expected in the area, as isolated rainfall totals could approach 9 inches in parts of Central Texas…