April Storm System Targets CA: See Timing, Impacts

CALIFORNIA — A unique late-April storm system will target California this weekend, bringing the potential for lingering downpours, thunderstorms and mountain snow to some parts of the state.

The system will move ashore through Saturday, creating a flow of cooler, moist air over the state, according to Accuweather forecasters. Rain fell over parts of Northern California's mountains and coastal areas Friday and is expected to move south into Saturday.

As the storm moves inland, showers will become more widespread over the rest of the state.

Forecasters at the San Francisco Chronicle said this weekend's storm system is unique because it's missing something that typically drives the most intense weather events in California — the jet stream.

"Instead, this weekend’s storm system is the atmospheric equivalent of a boat adrift at sea," forecasters wrote. "Meteorologists refer to this as a cutoff low, which is essentially a pool of cold air accompanied by a low-pressure center that’s broken away from the main flow of the jet stream."

Without the jet stream, the system is likely to linger through the weekend. Unlike a typical winter storm, this one isn't likely to bring much organized precipitation.

According to the National Weather Service office in Los Angeles, the SoCal area should see light rain early Saturday with a chance of thunderstorms over interior regions. Thunderstorms will be capable of producing brief, heavy downpours, small hail, gusty winds and lightning.

"Los Angeles will likely pick up a few hundredths to 0.15 of an inch of rain," AccuWeather Senior Meteorologist Chad Merrill said. "Los Angeles has only recorded a trace of rainfall this month, and that was April 3."

The system could also produce snow over higher elevations.

"In the central Sierra Nevada, snow levels will dip to around 5,500 feet for a time this weekend," Merrill said. "That's low enough for snow to fall and possibly stick over Donner Pass, California, along Interstate 80."

Meanwhile, light showers continued Saturday morning over portions of the Bay Area and Central Coast, according to the NWS. Forecasters said a small chance of thunderstorms remains for southern Monterey and San Benito Counties through Saturday afternoon.

A winter weather advisory is also in effect until 11 a.m. Sunday for Yosemite to Sequoia National Parks, according to the National Weather Service. Forecasters said the region could see snow accumulations up to 10 inches.

Looking ahead, cool conditions will linger over California and spread over more of the southwest later this weekend to early next week, Accuweather forecasters said.