A late-season storm out of the Gulf of Alaska will move into Southern California Tuesday and generate some rain and snow as well as high winds, but there is little danger of mud slides over slopes made bare by wildfires, National Weather Service forecasters said.
A cold front associated with that cold, low-pressure system is expected to bring three to six hours of steady rain — in San Luis Obispo and Santa Barbara counties Tuesday morning, then in Ventura and Los Angeles counties in the afternoon, according to an NWS statement. But there could be showers six to 12 hours before and after the passage of the cold front, it said, adding that “significant rain chances should end by late Tuesday night.”
Total rainfall amounts are expected to be between a quarter-inch and a half-inch in Los Angeles and Ventura counties, half the volume expected in San Luis Obispo and Santa Barbara counties, although up to one inch of rain may fall in the mountains and foothills, and between a quarter-inch and a third of an inch of rain per hour could come down when the rainfall reaches a peak, according to the NWS.
The snow level is expected to remain above 5,000 feet, although a dusting is possible at the 4,500-foot level, the NWS statement said.
Between two and four inches of snow are expected above 5,000 feet, although up to six inches is possible in some spots, forecasters said. Nonetheless, no weather-related difficulties or road closures are expected in the Interstate 5 Corridor as of this morning, they said.
Along with some precipitation, the approaching storm will generate high winds characterized by frequent gusts of between 30 and 40 miles per hour, with the occasional 50-mph gust in some mountain areas, according to the NWS.
“This storm should bring localized ponding of water on low-lying streets and highways due to clogged drains,” warned the NWS statement.’
“Wet oil-slicked roads due to the first significant rainfall in a while will impact the morning and afternoon commutes” Tuesday, it added.
The threat of mud and debris flows over slopes denuded by wildfire “is low,” although it should be monitored, the statement said.
Tuesday’s temperature highs are expected to be in the low 60s before they rise by a few degrees on Wednesday, back to today’s levels.