A Pacific Northwest rainstorm should arrive in Southern California on Friday afternoon, disrupting Halloween plans and setting the stage for dangerously slick road conditions.
The storm system is expected to bring rain, gusty winds, snow in the mountains and possible thunderstorms to the Southland as it moves down the California coastline, according to the National Weather Service.
Rainfall could reach as much as 1.5 inches along the Central Coast, with even higher amounts across northwestern San Luis Obispo County. Rainfall elsewhere is expected to be between a quarter-inch and three-quarters of an inch for most of the rest of the affected region.
National Weather Service specialist Stuart Seto said Los Angeles will be on the low end with only about a quarter-inch of rain. But even that amount is more than the area has had in months.
L.A. hasn't had a significant rainstorm since April 1, when one-tenth of an inch of rain was measured, Seto said.
Trick-or-treaters roaming the streets before sunset could see drizzle as early as 6 p.m., but the heaviest downpour won’t hit the area until closer to midnight, Seto said.
Most areas affected by the storm will receive between three and four hours of steady rain, according to the National Weather Service. And heavy downpours near the Colby burn area -- around foothill areas of Azusa and Glendora -- could cause minor mud and debris flows, forecasters warned.
“Everyone should be prepared to bundle up and have some kind of umbrella,” Seto said.
Since it hasn’t rained much in Southern California, the roads will be “extra slick due to months of oil buildup,” forecasters warned. Authorities were warning motorists to use extra caution on the roadways.
“Make sure you’re driving at safe speeds … and don’t drink and drive," CHP Southern Division spokesman Robert Meyer said.
Meanwhile, winds with gusts of up to 40 mph are expected to hit mountain regions, making travel on those roadways more challenging.
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