More than 20 counties in Kansas, including Douglas County, will be under a Flash Flood Watch this afternoon into Monday morning.

The National Weather Service in Topeka issued the watch, which will extend from 4 p.m. Sunday until 7 a.m. Monday.

According to the weather service, scattered thunderstorms are expected to develop this afternoon and become widespread overnight. The storms will produce periods of very heavy rain, with potential for multiple rounds of storms to affect some areas.

Widespread rain is expected with localized heavy amounts up to 3 inches. Saturated ground conditions and existing high stream flows will cause flash flooding to occur quickly in areas receiving heavy rain.

Flash flood watches mean that rapidly developing floods are possible but not imminent in the area.