An overnight deluge that dumped several inches of rain in the coastal hills of Sonoma County set the stage for flash flooding in some creek areas and covered low-lying intersections around Sonoma County in water early Friday, trapping several motorists who entered.
A flash flood warning was in effect for all of Sonoma County, with special concern about areas of Penngrove and Temelec, near Sonoma, the National Weather Service said.
Automatic gauges indicated flooding already was occurring on Willow Brook Creek in Penngrove, and the water would continue to rise, the National Weather Service said.
Montgomery School in Cazadero was closed for the day, school officials said.
All other schools in Sonoma County are open, County Superintendent Steve Herrington said.