Emergency management directors with the National Weather Service Charleston will hold a briefing Tuesday regarding changes to flash flooding event criteria.

Flash flooding could happen at any moment from the storm in the Knoxville area, the National Weather Service has warned.

Significant rainfall from storms caused flash flooding in parts of Montgomery County, Maryland, located north of Washington, D.C., on Saturday, trapping many in buildings and cars.

Democrats have questioned the effectiveness of the flash flood warning the weather service sent out on July 4, after floodwaters had already overwhelmed many areas in Kerr County.

The Johnson County creek, where the woman was walking, surged 6 feet in 30 minutes as storms dumped heavy rains in the Kansas City area.