LOS ANGELES (CBS) — The National Weather Service has issued a flash flood watch for the mountains and Antelope Valley.

The watch, which went into effect at noon Saturday, is set to expire by 8 p.m.

Forecasters say scattered thunderstorms are likely to develop by afternoon across the Antelope Valley and Los Angeles County mountains, but not into the Santa Monica range.

A flash flood watch means that conditions may develop that lead to flash flood.

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