The latest in a seemingly endless parade of winter storms is beginning to ease in California, slogging eastward Wednesday after unleashing damaging winds that cut power to more than 250,000 customers and led to at least two fatalities Tuesday.
The winds, which gusted up to 70 mph at the coast and over 100 mph near mountain summits, downed scores of trees and power lines, some of which blocked roads and toppled onto vehicles. The strong gusts also stirred up the ocean, sending big waves crashing into the coast.
The San Francisco and Monterey Bay Area were among the hardest hit by the storm, but much of the southern two-thirds of the state endured both strong winds and heavy precipitation. Rain showers lingered Wednesday morning following widespread amounts of at least 1 to 3 inches from the Bay Area to San Diego, which set records in some instances and triggered flooding and the need for high-water rescues. Some additional snow was also expected Wednesday in the mountains, many of which have seen historic amounts this season.
The images below help illustrate both the storm’s strength — which set March records — and its sweeping impacts across the state.
Hurricane-like but not a hurricane
Last several hours of radar data out of San Francisco via @RadarOmega
— Steve Copertino (@TheSteveCop) March 21, 2023
Can't say I've seen two meso-lows Fujiwara off the California coast like this before. Numerous reports of wind damage have been coming in as these produced gusts of around 60 - 80 mph. #CAwx pic.twitter.com/FfJOCXdI2y
Weather watchers were in awe through much of Tuesday as intense zones of low pressure swirled menacingly just offshore near the San Francisco and Monterey Bay areas.
The low-pressure centers — some containing hurricane-like eyes — exhibited what’s known as the Fujiwhara effect, in which storms cycle around each another before sometimes merging or going separate ways. In this case, the low-pressure zones consolidated as they made landfall near San Francisco.
Satellite and radar imagery revealed a region of clearing near the storm center, which allowed an interval of blue skies and sunshine as the center of the storm moved overhead.
We're in the eye of the storm. Never seen one like this in SF.#cawx pic.twitter.com/DnAVmYFcY0
— Emey (@emeyerson) March 21, 2023
While displaying some hurricane-like characteristics, this was no hurricane, as it was powered by temperature contrasts rather than warm ocean waters.
Before coming ashore, the storm strengthened fast enough to be considered a marginal example of a “bomb cyclone,” as its central pressure plummeted; the lower the pressure, the stronger the storm. San Francisco set a March low-pressure record, a testament to the storm’s unusual might.
Punishing winds
The rapidly developing storm delivered a high-end windstorm as it crashed ashore.
The National Weather Service’s office serving the Bay Area issued rare severe thunderstorm warnings for destructive winds up to 80 mph, also activating wireless alerts. Even though the storm contained little to no lightning, the high-level warning allowed the Weather Service to call extra attention to the dangerous conditions.
Gusts of 60 to 80 mph were common near the storm center, while high elevations in central and Southern California observed gusts over 100 mph, including 105 mph at San Guillermo and 118 mph at Hopper Canyon.
RIP Palm Trees 🌴 on Dolores Street #CAwx pic.twitter.com/QX2jBUjgxt
— Jeremy (@JeremyR1992) March 22, 2023
Additionally, it’s possible a tornado or two touched down in the southland. Warnings were issued and video suggests that at least one weak twister spun up near Carpinteria.
A dousing up and down the coast
About 1 to 3 inches of rain was recorded across most of the Bay Area near where the storm center came ashore. Some locations in the hilly terrain south of San Jose picked up as much as 4 to 5 inches of rain.
Around Los Angeles, at least five rainfall records were set for March 21, according to the Weather Service. This included downtown Los Angeles, where 1.43 inches was recorded, beating a record from 1893.
Even locations south of the Mexico border saw a hefty dousing. Totals around 2 inches or more reached the international border, with around an inch in San Diego, where there were reports of flooding.
Rainfall totals along California’s coastal ranges are now reaching eye-popping totals for the season, including over 100 inches of rain in the hills around San Jose and Monterey.
67 feet of snow
Snow rates went nuclear for a time this morning here in Mammoth! Awesome! ❄️ pic.twitter.com/3kQni1J2me
— Carter Murphy 💰8️⃣ (@cartermurphy218) March 22, 2023
The storm unloaded additional 1 to 3 feet of snow to the Sierra, and flakes even accumulated at lower elevations into southern parts of the state. As much as another foot is possible Wednesday before the storm fully winds down.
Fresh powder pushed the snow total at the summit of Mammoth Mountain over 800 inches (67 feet) on the season. “That’s enough to bury three and a half giraffes standing on each other. Or ten Michael Jordans,” wrote Snow Brains, a website for skiers.
The mountain is closing in on its snowiest season on record after piling up 55 feet of snow at the main lodge. The resort expects skiing to continue through at least late July.
After 3 inches of powder Tuesday night, Bear Valley Resort — also in the Sierra — reported its seasonal snow total reached 640 inches, most on record.
In the mountains of Southern California east of Los Angeles, the storm produced up to 20 to 40 inches of snow through Tuesday morning, mainly above 6,000 feet in elevation.
Raging waters
As the storm came in, conditions were intense at the coast, and not just the open beaches. San Francisco Bay was sloshing like a giant bathtub, and some ferries were unable to safely dock due to the waves.
Rivers such as the Merced are full, prompting flood watches in the Central Valley, where some farms look like lakes. Water releases from brimming reservoirs are exacerbating high river flows in the region.
Typically dry creek beds and riverbeds in southern parts of the state also proved dangerous Tuesday.
Water rescue underway in Devore, near Cajon and Swarthout Canyon. The driver went through swift moving water and lost control. He got out, and is now on the bank on the other side. @SBCOUNTYFIRE trying to figure out how to get to him to bring him to safety. pic.twitter.com/fDw5UftW67
— Rob McMillan (@abc7robmcmillan) March 21, 2023
The next in a seemingly nonstop storm train arrives late this weekend or early next week. As more storms arrive and mountain snows melt, flooding promises to be a serious concern deep into spring.
Jason Samenow contributed to this report.