The areas of impact include George West, Lake Bryan, Wixon Valley and Mooring.
Residents have been told to seek shelter at low points.
Wind and hail damage is expected to affect vehicles, roofs and trees.
Tornado HQ said: “For your protection move to an interior room on the lowest floor of a building.
“Torrential rainfall is occurring with this storm and may lead to flash flooding.
“Do not drive your vehicle through flooded roadways.
“Mobile homes will be damaged or destroyed.”
The warning is in place until 10.45pm UTC (5.45am BST).
There are reports of damage to homes and businesses in Bryan, according to KHOU TV.
More to follow…
source: express.co.uk