Will La Niña bring more rain to California?

(NEXSTAR) – California’s rainy season has already begun, but the upcoming La Niña could shake things up.

La Niña is expected to form between now and December and last until early 2025, according to the Climate Prediction Center. As La Niña approaches its peak in winter, its influence on weather patterns becomes stronger.

The phenomenon typically splits the country in two, bringing a dry winter to the southern half and a wetter winter to the northern half. The difficult thing is that we don’t know exactly where that dividing line will be.

Sometimes La Niña also splits California in two, producing mixed results: lots of rain in Northern California and drought in Southern California. But in recent La Niña years, the dividing line has moved further north, bringing tons of rain and snow to Oregon and Washington but devastating drought conditions to nearly the entire Golden State.

Where that line will go remains to be seen, but there is reason to believe we could see more rain — not less — in California, said Nexstar chief meteorologist Brian James.

“Typically, the northern half of the state has a better chance of benefiting from a La Niña pattern than the central-southern part of the state. However, it is a weak La Niña,” he emphasized. That would make it more likely that the jet stream would be pulled further south into California, and the wall keeping cold air out would be thinner and weaker.

“That would also mean that it’s more likely that some of that moisture will be pulled further into the state, so it’s not just the northern half of the state that’s benefiting,” James explained. “It could certainly have an impact and be beneficial to a larger portion of the state.”

As long as the rain doesn’t fall too hard or too fast, a wet winter is usually a good thing for California. The state receives most of its rainfall during the winter months.

“In California, there are very few situations where rain is not welcome,” James said.

Weak La Niña winters could also be better for California’s snowpack, a recent analysis by NOAA meteorologist Tom Di Liberto found. A review of weather data since 1959 found that the California mountain ranges received more snow in weak La Niña years than in all La Niña years.

This season’s drought outlook is also good for much of the state. Only the far southern desert areas along the California-Arizona border were identified as areas of serious concern.

But trends are never a guarantee, and there are many other forces at play besides La Niña. For example, climate change is causing the amount of snow in most parts of the United States to decline sharply. Even a freak snowstorm can always appear and defy all odds.