A mesoscale convective vortex developed overnight and with daytime heating generated strong thunderstorms during the morning. Some of these storms produced tornadoes and heavy rain that led to flash flooding.

Tornado in BASTROP, TEXAS
From 12-MAY-20 09:54:00 to 12-MAY-20 10:01:00 (CST-6)
Location: SMITHVILLE MUNI ARPT
Tornado F-scale: EF0
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A National Weather Service damage survey concluded that a weak EF0 tornado formed just south of the Colorado River near Smithville on FM 2571. There it produced tree damage and some visible wind damage to a few residences along FM 2571. The tornado moved northeast and crossed Hidden Shores Road where more tree damage was observed. The tornado then crossed the river before dissipating near the intersection of Highway 71 and Kellar Road. Maximum winds were estimated at 80 mph.

Tornado in CALDWELL, TEXAS
From 12-MAY-20 08:09:00 to 12-MAY-20 08:11:00 (CST-6)
Location: MC MAHAN
Tornado F-scale: EF0
Property damage: 10.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A National Weather Service survey concluded that a weak and short lived EF0 tornado touched down near the intersection of FM 86 and CR 713 in McMahan. The small tornado moved north across an open field before hitting a residence where it damaged trees, along with the roof of a barn. The tornado dissipated to the north of the property. Maximum winds were estimated at 85 mph.

Tornado in BASTROP, TEXAS
From 12-MAY-20 10:28:00 to 12-MAY-20 10:28:00 (CST-6)
Location: PAIGE
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

A storm chaser reported a brief tornado just west of FM 2104 south of Paige.

Flash Flood in COMAL, TEXAS
From 12-MAY-20 11:11:00 to 12-MAY-20 13:30:00 (CST-6)
Location: SMITHSON VLY
Flood cause: Heavy Rain
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorms produced heavy rain that led to flash flooding. The Guadalupe Blanco River Authority rain gauge at Startzville recorded 13.01 inches of rain between 7 am and 1 pm. Several inches of water flooded the Lowes Market in Startzville and several cars in the parking lot were partially submerged.

Flash Flood in TRAVIS, TEXAS
From 12-MAY-20 11:48:00 to 12-MAY-20 14:00:00 (CST-6)
Location: BLUFF SPGS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Local Official

Thunderstorms produced heavy rain that led to flash flooding. Austin Flood Early Warning System(FEWS) reported Old San Antonio Rd. near Slaughter Creek was closed by flood water in South Austin. CoCoRAHS observers reported 4 to 4 1/2 inches of rain in the area.

Flash Flood in DE WITT, TEXAS
From 12-MAY-20 19:26:00 to 12-MAY-20 22:00:00 (CST-6)
Location: YORKTOWN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorms produced heavy rain that led to flash flooding closing roads in and around Yorktown. CoCoRAHS observers reported 2.5 to 3.5 inches of rain in the area.

Flash Flood in DE WITT, TEXAS
From 12-MAY-20 19:26:00 to 12-MAY-20 22:00:00 (CST-6)
Location: CUERO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorms produced heavy rain that led to flash flooding closing roads in and around Cuero. CoCoRAHS observers reported 2.5 to 3.5 inches of rain in the area.