LOS ANGELES (CBSLA.com) — An unseasonably cold storm expected to generate strong winds is headed for Southern California Wednesday, with rain expected beginning Thursday afternoon and possibly lasting until Friday night.

The storm, which originated in the Gulf of Alaska, may trigger rainfall in Northern California as early as Wednesday night, National Weather Service forecasters said.

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Between a quarter-inch and an inch of rain, which higher amounts likely in Los Angeles County, is expected to fall, according to the NWS. But in the San Gabriel Mountains and in any area hit by a thunderstorm, up to an inch-and-a-half of rain is possible, it said.

The chance of thunderstorms is slight, but any that materializes will have the potential for some minor mud and debris flows, forecasters said.

In Glendora, officials raised the alert status to “yellow” for residents living below the Colby Fire burn area, requiring residents to remove vehicles, trash containers and obstacles from streets to protect against damage from possible flooding or mud flows and to clear streets for emergency crews.

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The snow level generally will range between 5,000 and 6,000 feet, and between four and eight inches of snow is expected in the San Gabriels, about twice as much as in Ventura County, L.A. County’s neighbor, forecasters said.

Also expected as an outcome of the storm are gusty southwest winds that could gust at 50 mph in the San Gabriels and the Antelope Valley, they said.

Wednesday’s high temperatures in the Southland are expected to be in the high 60s and low 70s under cloudy skies. Thursday’s will be a few degrees lower in many communities.

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