What to Know
- Flood watches are in effect for a widespread area in Southern California.
- The heaviest rain arrived Saturday morning with scattered showers and thunderstorms in the afternoon and evening forecast.
- More rain is in the Easter Sunday forecast with temperatures well below normal.
A slow-moving spring storm delivered hours of steady rain overnight and into Saturday morning at the start of a wet Easter holiday weekend in Southern California.
A flash flood warning was issued for parts of Los Angeles County, including downtown LA, Santa Monica, Long Beach, Glendale, Malibu, the South Bay and other areas. The warning was set to expire at 8 a.m., but flood watches will remain in effect throughout Southern California.
An inch of rainfall fell overnight in downtown Los Angeles.
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A less severe flood advisory was in effect for parts of LA County until 9:15 a.m. and in Orange County until 10:45 a.m.
The heaviest rain was expected early Saturday as the storm lashes the region with strong winds. Mountain communities can expect snow and hazardous driving conditions at the end of California's wet season.
Over the past 30 years, there have been only four rainy Easter holidays in Los Angeles -- 2020, 2013, 2010 and 1995. In 1995, LA received more than a half-inch of rain on Easter, which fell on April 16 that year.
An evacuation order was issued late Friday morning for part of Ventura County. The order includes the unincorporated area of Santa Paula along State Route 150, which will stay closed for several months, due to the possibility of more landslides.
Flood watches went into effect Friday evening for widespread parts of Southern California, including Los Angeles County, inland Orange County, San Bernardino and Riverside counties, and the Ventura County coast. More severe flash flooding warnings could be issued as the storm settles in over the region during the weekend.
A winter storm warning will be in effect through Sunday night for the Ventura County and San Gabriel Mountains. San Bernardino and Riverside county mountains are under a winter storm watch, but that could be elevated to a warning.
The wet weather forecast has already forced the cancellation or postponement of several Easter weekend events, including all races at Santa Anita Park in Arcadia and Egg Bowl at the Rose Bowl.
Here's what the wet and windy weather means for the Easter holiday weekend in Southern California.
Easter weekend storm timeline
The most significant rainfall was overnight early Saturday. After a night of gusty winds reaching up to 45 mph in the mountains and deserts, rain became steadier during the overnight and into early Saturday morning.
"(Saturday) morning, that's when the heaviest of the rain is going to arrive," said NBCLA meteorologist David Biggar.
A line of heavy rain moved from west to east Saturday morning across the Los Angeles region. That front slid slowly across the region for several hours and brought heavy rain for an extended period in parts of Ventura and Los Angeles counties.
By Sunday, scattered showers will develop, but there's a chance for isolated thunderstorms with the threat of lightning, hail and heavy downpours. Even brief downpours could bring the threat of flash flooding.
“The threat for flooding will continue through (Sunday) evening,” said NBCLA’s Belen De Leon.
Rain totals are expected to range from 1 to 3 inches in most areas with more than 3 inches possible in foothill and mountain communities. Any additional rain on hillsides soaked during Southern California's winter storms will raise the risk of slides and flooding.
"The ground, while drier than February, still has quite a bit of moisture in it, so it may not take much heavy rainfall to create some flooding problems," said Biggar. "I’d expect to see our typical roadway flooding issues around the region on Saturday morning. There will probably be some minor rockslides and debris flows around steeper canyon roadways."
The Los Angeles Fire Department received hundreds of landslide reports during the early February storm, including along Mulholland Drive and in Topanga Canyon, which remains too unstable for work crews. Parts of both canyon roads remain closed with more rain on the way.
As for snowfall, 1 to 2 feet are possible above 6,500 feet. Snow and gusty winds could affect travel in mountain passes. Snow levels will drop from 5,500 to 6,000 feet early Saturday to around 4,500 feet Saturday night.
The average high temperature on Easter in Los Angeles is 71 degrees, but weekend temperatures will dip to well below normal.
The storm will draw moisture from a weak atmospheric river over the Pacific as it moves toward California. The rivers of moisture in the sky have fueled some of Southern California's most powerful storms, including the multi-day system that produced record rainfall earlier this year.
Los Angeles' average rainfall for March is 2.23 inches. As of Friday morning, LA received 1.39 inches of rain as Southern California nears the end of its wet season. This weekend's rain will likely push the month's total above the average.