AUSTIN (KXAN) — Although most of Sunday’s severe weather stayed west of Central Texas, one severe storm clipped the northern portion of San Saba County. Strange enough, it was actually on the other side of the KXAN viewing area did we see reports of damage though.
So what happened?
Early Monday morning, a complex of storms moved west to east across the San Antonio metro. In its wake, an area of low pressure formed as air sank on the backside of the complex of storms. The sinking air then warmed (formally called adiabatic warming) and became less dense, creating a tight pressure gradient between the low pressure and the complex of storms. This pressure gradient then caused air to accelerate (as pressure gradients do), resulting in damaging wind gusts across portions of Comal, Guadalupe and Caldwell counties.
This microscale weather feature is known as a wake low.
These events are very localized and difficult to forecast.
- New Braunfels Municipal Airport: 71 mph
- Luling: 55 mph
- Randolph Air Force Base: 53 mph
- Bracken Bat Cave: 48 mph
Minor damage was reported in Luling (Caldwell), Lockhart (Caldwell) and Cistern (Fayette).
The Caldwell County Office of Emergency Management told KXAN in a statement there was some wind damage in the Luling area, with reports of roof shingles being blown off and downed power lines and trees. No injuries were reported though, the office said.
Below is a radar image showing inbound and outbound velocities at the KEWX radar in New Braunfels. From our counterparts at the National Weather Service Austin/San Antonio:
“That tightened pressure gradient (pink lines in image) also line up with the highest velocity (bright green/light blue) observed by the KEWX radar. These events are difficult to predict, especially close to a radar, and occur in the stratiform light rain behind storms.”