A day of blustery and spotty weather - with some areas sunny and others soaked - ended with strong thunderstorms bearing down on parts of Southern California.
A cold, low-pressure system was expected to move southeast over Southern California through Monday, the National Weather Service said.
Heavy rain, hail, lightning and gusty winds were expected overnight.
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A flash flood warning was issued for central Ventura County on Sunday afternoon as two separate, strong thunderstorms developed over the region, the NWS said. The warning expired at 7:30 p.m. Locations in the warning included Camarillo, Santa Rosa Valley, Moorpark and Somis.
The heaviest rain was in Ventura County, just west of the LA County line, the NWS said. A "heavy downpour" was spotted just north of the 101 Freeway near Camarillo, and heavy rain was falling on state Route 118 west of Moorpark.
“It’s been crazy, we’ve seen a lot of lightning strikes,” said Sherman Oaks resident Jordan Orenge. “I’d appreciate a little less rain more often than all the rain at once. It was like a shower just unloaded on us today.”
Scattered showers had been forecasted throughout the weekend as a winter storm stuck around in Southern California, but little sustained rain had fallen outside of the mountains and foothills until about 2 p.m. Sunday, when the storms developed.
"A moist and unstable air mass in place from a cold upper low pressure system will bring showers and a slight chance of thunderstorms to the area through Monday,'' the NWS said in a statement released at 2:09 p.m.
"A weaker storm system will follow on its heels later Monday, allowing for lingering showers into early Tuesday," the NWS said.
Hail was reported in some areas, including by NBC4 meteorologist Crystal Egger. Rain and thunder were also reported.
The storm between Ventura and Ojai would bring heavy rains, while the one over Santa Monica was expected to briefly bring heavy rain, the NWS said.
The City News Service contributed to this report. Refresh this page for updates on this developing story.