State Route 78 was closed between Scissors Crossing and Imperial Canyon, and rocks and mud were also reported covering pavement on County Road S-2 from Scissors Crossing to Ocotillo Wells.
Heavy rain was also spotted north of Mount Palomar, in the Idyllwild area.
Scattered showers and thundershowers in the mountains and deserts were to linger through Monday afternoon, with a flash flood watch in effect, a National Weather Service forecaster said.
“Thunderstorms and showers, some locally heavy with 1 to 2 inches of rain and possibly even more,” began about 12:30 p.m. and will last throughout the afternoon,” NWS forecaster Mike Watkins said.
Rainy conditions were due to normal summer monsoonal moisture, and the remnants of Tropical Storm Ivo.