Southern California was expected to be hit Wednesday with a cold front from Alaska that is set to move inland and bring widespread rain, gusty winds, colder temperatures and mountain snowfall.
The Pacific storm coming out of the Gulf of Alaska was predicted to arrive in Ventura and Los Angeles counties Wednesday afternoon or evening and continue to move across the region.
National Weather Service forecasters said the storm would bring steady rain when it hits the area, followed by showers overnight and a slight chance of thunderstorms and small hail on Thursday. The service issued a hazardous weather outlook for southwestern California.
About 1/2 inch of rainfall is expected in coastal, valley and inlands areas, with 1 inch expected in the foothills and mountains.
Snow levels may drop as low as 3,500 feet by Thursday morning, with up to 1 foot in snow falling at the highest elevations.
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Some roads in the Angeles National Forest were set to be closed Wednesday evening. The eastern San Gabriel Mountains and the San Bernardino Mountains were expected to get the bulk of the snow.
Overnight, a dusting of snow may hit the Golden State (5) Freeway as it passes over the Grapevine. The weather service warned of "hazardous driving conditions," and said reduced visibility may be caused by precipitation and/or gusty winds of up to 45 mph in the San Bernardino Mountains and high deserts.
"The motoring public needs to understand that they need to actually plan ahead, give themselves a little bit more time to travel, slow down, and of course buckle up," said California Highway Patrol spokesman Officer John Lutz.
Lutz said he didn't expected the 5 Freeway to be closed over the Grapevine.
A winter-weather advisory was set to go into effect later Wednesday for the mountains of San Bernardino, Riverside and San Diego counties.
Daytime temperatures may drop to 10 to 20 degrees below normal on Thursday, the service said.
"The combination of wet snow and low temperatures in the mountains could create a dangerous situation for campers and outdoor enthusiasts that are not prepared for the change in the weather conditions," the weather service warned.
The Los Angeles County Public Works Department will close the following roads at 10 p.m.:
- Angeles Forest Highway from Upper Big Tujunga Canyon Road to Aliso Canyon Road; and
- Upper Big Tujunga Canyon Road from Angeles Forest Highway to Angeles Crest Highway.
The closures will be in effect until the storm has passed. More information is available at www.dpwcare.org.
Conditions should dry out during the daytime Friday, and then a weaker storm system may bring precipitation that night and into Saturday. More rain may following Sunday and Monday morning.