Friday September 23, 2022
San Francisco Chronicle —
This September has been a relatively wet month for the Bay Area. Remnants of Tropical Storm Kay brought moisture to Northern California earlier this month. More recently, an unusual storm delivered nearly 3 inches of rain to the Sonoma Coast and about a third of an inch to downtown San Francisco.
But the next few months will probably be drier than normal for much of California, as La Niña conditions will likely extend through a third consecutive winter — only the third such “triple-dip” since the 1950s.
“Getting what we call a double-dip La Niña is not totally uncommon. But triple dips are much more uncommon,” said Michelle L’Heureux, a climate scientist with the National Oceanic and Atmospheric Administration’s Climate Prediction Center. Forecasters are giving a greater than 60% chance that La Niña will continue through winter, or the December-February period.
La Niña is a climate pattern resulting from cooler-than-normal sea surface temperatures in the eastern Pacific close to the equator. Its counterpart is El Niño, when the temperatures are above normal. Together, these two events make up the El Niño-Southern Oscillation, also known as ENSO, and influence temperatures and precipitation around the planet.