SAN DIEGO (FOX 5/KUSI) -- Parts of eastern San Diego County, including Alpine, Descanso and Mount Laguna, will be under a Flash Flood Warning through Monday afternoon, the National Weather Service reports.

Doppler radar picked up thunderstorms and heavy rain in the area around 12:40 p.m., according to the National Weather Service, which warned that the area is expected to see up to 1 inch of rain per hour and that flash flooding is possible until 3:45 p.m. Monday.

NWS reports around 0.75 and 1.5 inches of rain have already fallen in the area and additional rainfall of 0.5 to 1.75 inches is possible for areas in eastern San Diego County, including Alpine, Cuyamaca Rancho State Park, Descanso, Pine Valley, Hwy S1 between Lake Cuyamaca and Mount Laguna, Guatay, Boulder Creek and Japatul Val

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