Map Shows Millions Bracing For More Heavy Rain in California

Millions of Americans are bracing for another round of rain that is expected to arrive less than two weeks after torrential rain left California in a sodden state.

Several atmospheric rivers have battered the state this month, with the most recent storm arriving in northern California on Sunday and moving south through the state throughout this week. Although the rain has proven beneficial to the state's drought, the storms have caused devastating floods and landslides. More rain is on the way for northern California, according to a map by the National Weather Service (NWS) Climate Prediction Center.

Atmospheric rivers are defined as a "long, narrow region in the atmosphere—like rivers in the sky—that transport most of the water vapor outside of the tropics," according to the National Oceanic and Atmospheric Administration.

"After a welcome break, moderate to locally heavy precipitation returns to Northern California later next week, leading to possible flooding in lower elevations and heavy snow at higher elevations," the Climate Prediction Center posted on X, formerly Twitter, on Wednesday.

The map predicted heavy precipitation for the northern half of the state and a small piece of southern Oregon from February 29 to March 1. Possible flooding threatens a smaller area of the state within the heavy precipitation border, and heavy snow is expected in the mountains, although a National Oceanic and Atmospheric Administration (NOAA) spokesperson told Newsweek that the predictions don't anticipate catastrophic flooding.

However, the incoming rain isn't associated with an atmospheric river event.

"This event would probably not be categorized as an atmospheric river event. The precipitation is related to a deep mid-level low-pressure system (trough) that is situated along the West Coast," the NOAA spokesperson told Newsweek.

An 8- to 14-day precipitation outlook map of the U.S. on the NWS Climate Prediction Center website shows that above-average precipitation is expected for northern California and southwestern Oregon, with a slightly smaller chance of above-average precipitation expected for the northwestern U.S., including from Washington south through California and Nevada and east to encompass all of Idaho and northwestern Utah.

The incoming rain could be beneficial for California's two biggest reservoirs, Lake Shasta and Lake Oroville, both in the northern part of the state. The most recent atmospheric river boosted the lakes' water levels by several feet.

Both lakes are in a significantly improved condition compared to the summer of 2022 when the water reached concerningly low levels.

As of Thursday morning, Lake Shasta was only 20 feet below full pool. Lake Oroville was nearly 43 feet below full pool.

NWS meteorologist Mike Wofford previously told Newsweek that El Niño could be the reason the state has received more rain than normal. El Niño is one of two climate patterns that greatly influences the Earth's weather.

"Going into the winter, the expectation was that we would have higher rain amounts due to the El Niño situation in the Pacific," Wofford said. "That tends to bring storms farther south and pull in more moisture."