What led to California’s drought-busting rain this winter?.
“It has been a very interesting winter across most of the United States with very stormy and chilly weather in the West,” AccuWeather Long-Range Forecaster Jack Boston said.
La Niña occurs when ocean water temperature are below normal across the central and eastern Pacific Ocean near the equator.
However, there are many other phenomena that occur that can influence the global weather pattern besides La Niña or El Niño.
“The factor that has caused all of the storminess in California this season seems to be an unusual sea surface temperature distribution in the Pacific Ocean,” Boston said.
While El Niño usually favors stormy weather for California, warm water off the coast sent the systems on a more northerly track, missing out on the drought-stricken state.
Water temperatures in this region fell drastically since last winter, allowing storms to track farther south and drop heavy rain and mountain snow over California.
The heavy rain and mountain snow was a double-edged sword for the state, helping to alleviate the severe drought but also triggering flooding, mudslides and avalanches.
Officials also opened the spillway to the Don Pedro water reservoir for the first time in 20 years to prevent water from flowing over the dam’s uncontrolled spillway.
“The rain and snow this winter, especially during January, was a huge help in the short and long-term drought,” AccuWeather Western Weather Expert Ken Clark said.