Los Angeles — Record flooding over three days dumped more than a foot of rain on parts of Northern California, a fire left thousands of people under evacuation orders and warnings in Los Angeles County, meteorologists issued the first tornado warning in San Francisco and rough seas brought down part of a pier in Santa Cruz.
All of this extreme weather has hit California in recent weeks, showing the state’s particular vulnerability to major weather disasters.
On Tuesday, strong storms produced waves that forecasters said could reach 35 feet around Santa Cruz. He National Weather Service (SNM) issued a high surf warning through the afternoon, warning people to stay away from the ocean and docks.
For Chandler Price, a meteorologist at SNM in San Diego, these extreme weather events are both typical and unusual for a La Niña winter, a natural climate cycle that can cause extreme weather conditions across the planet. In California, it means a wetter-than-normal northern region and a drier south.
“So far we’ve seen that pattern play out pretty well,” he said, but added: “obviously, you know, the tornado in the Bay Area was an outlier…We haven’t seen that before, at least not for a long time.” ”.
Storm and wind gusts up to 60 mph prompted San Francisco tornado warning that spread to neighboring San Mateo Countywhich aired to around a million people earlier this month. The tornado overturned cars and downed trees and power poles near a shopping center in Scott Valley, about 68 miles south of San Francisco, injuring several people. Tornadoes occur in California, but they rarely hit populated areas.
In San Francisco, local meteorologists said straight-line winds, not a tornado, toppled trees onto cars and streets and damaged roofs.
The storm also dumped a significant amount of snow in the northern Sierra Nevada.
F. Martin Ralph, director of the Center for Climate and Western Aquatic Extremes at the University of California, San Diego, said that Climate change means that atmospheric rivers, long stretches of moist air that can produce heavy rain, will be responsible for a greater proportion of the country’s annual precipitation. California and the periods between those major events will be drier. These storms are essential for water supplies, but they can also be dangerous.
“When they are too strong and too many in a row, we end up having floods,” he said, adding that they drive California’s climate extremes.
During this week’s storms in Santa Cruz, one man was trapped under debris and died, and another person was swept into the ocean. The waves also dislodged the end of a Santa Cruz municipal pier that was under construction, and three people fell into the ocean. One swam to shore and the other two were rescued.
A series of atmospheric rivers are expected during the rest of the week. Overall, this pattern is not unusual: These storms regularly produce high winds, heavy snowfall in the mountains, and torrential rain at this time of year.
“What’s a little unique about this configuration is how closely spaced they are, so there’s not a lot of separation between them,” said David Lawrence, a meteorologist and emergency response specialist with the National Weather Service.
Also There were severe storms in the state before Thanksgiving Daywhich dumped more than a foot of rain on Santa Rosa over three record-breaking daysaccording to federal meteorologists.
But these storms have not spread far south, creating dry weather in Southern California that increases the risk of fires.
One of the state’s most recent fires, the Franklin Fire, left about 20,000 people under evacuation orders and warnings and forced Pepperdine University students to shelter in place. The fire was fueled by the Santa Ana winds, the famous seasonal winds that blow dry air from the interior toward the coast, pushing back moist ocean breezes.
Most of the destruction occurred in Malibu, a community in the western corner of Los Angeles known for its beautiful cliffs and Hollywood’s famous Zuma Beach. The fire damaged or destroyed 48 structures and is one of nearly 8,000 wildfires that have burned more than 1 million acres in the Golden State this year.
The Santa Ana winds, which peak in December, have also contributed to warmer-than-average temperatures in parts of the southern state, said the National Weather Service’s Price.
“Eighty-degree Christmases aren’t entirely uncommon around here,” he added, but “there were a couple of record high temperatures in the mountains, which are generally less affected by the Santa Anas, so they were a little unusual.” ”.