There was no way to predict El Niño back then. “The bottom line is that if you count every El Niño as wet and every La Niña as dry, sooner or later you’re gonna get embarrassed.”Ī big reason why El Niño and La Niña are so fixed in the minds of many Californians as the crystal ball of winter weather is how the science developed in the 1980s and ’90s after particularly punishing winter storms in 1982–83. For instance, during La Niña seasons since the 1950s, coastal Southern California got just 80% of its average annual rainfall, while the San Francisco Bay Area got 93%, according to Null’s website. If you look at all the La Niña events over roughly the last 75 years, Southern California does tend to get below-average rainfall, while for Northern California, it’s more a roll of the dice. Null, an adjunct professor at San Jose State’s Department of Meteorology and Climate Sciences, has put together data comparing La Niña and El Niño years and what they’ve meant - or not - for California’s precipitation. rainfall? Almost anything!”įour months ago, he again tweeted: “Does La Niña automatically mean another dry winter for California? Not necessarily.” In late 2020, as La Niña was developing, he tweeted of the phenomenon: “What does it mean for California and U.S.
One meteorologist who has warned against putting too many eggs in the La Niña basket is Jan Null, a former lead forecaster for the National Weather Service. Drought Monitorĭeep splotches of dark red and purple signifying the worst levels of drought have been erased from California’s map, thanks to a series of powerful storms. Taking the midpoint of that forecast - say, 40% - that meant there was a 35% probability of near-normal precipitation and a 25% chance of above-normal precipitation, said David DeWitt, director of the Climate Prediction Center.Ĭalifornia Nearly all of California exits the worst drought categories in U.S. But for Southern California, the agency reported there was a 33% to 50% chance of below-normal precipitation. The center’s seasonal forecast for December, January and February said there were equal chances of a dry or wet season in Northern California. And California had already recorded its three driest years in the historical record. The forecast in October by the Climate Prediction Center, a division of the National Weather Service, indicated the odds were stacked against the Golden State: a rare third year of La Niña was expected. Though winter isn’t over, and a renewed dry spell can’t be ruled out, the significant storms have defied expectations of a dry winter.Ĭlimate & Environment For all their ferocity, California storms were not likely caused by global warming, experts sayĮxperts say California’s recent series of storms was no more severe than what the state has experienced in the last century. Downtown Los Angeles has logged more than 13 inches of rain since October - more than 90% of its annual average of 14.25 inches. San Francisco was drenched with more than 18 inches of rain since Christmas, posting its wettest 22-day period since 1862. The Sierra Nevada has a snowpack of 240% of average for the date, and 126% of where it should be by the start of April. Despite La Niña’s presence, a robust series of 10 storms brought impressive precipitation across California, spurring floods and landslides, increasing reservoir levels and dumping eye-popping snowfall in the mountains.
El Niño - a warming of sea-surface temperatures in the tropical Pacific - seemed synonymous with wet winters for Southern California, while La Niña was a heralder of drought.īut the would-be model didn’t hold up this winter.
For decades, two climate patterns in the Pacific Ocean have loomed large in predicting weather in California and other parts of the globe.