• Rain already falling in California from the first system
  • Mississippi Valley next in line for storm's heavy rains

The West Coast could get nearly 20 inches (51 centimeters) of rain in the next week and the lower Mississippi Valley, which saw flooding in January, could get half as much as a series of El Nino-spurred storms begin to slam into the U.S.

The first storm will soak the entire West Coast, as well as drop snow by the foot in the mountains, before moving into the central U.S. and stalling next week, said Louis Uccellini, director of the National Weather Service. It will likely be followed by a second system.

“These storms and their intensity are consistent with the El Nino pattern,” Uccellini said in a conference call with reporters Friday. “El Nino remains strong and continues to influence weather patterns.”

The first round has already started in California and has the potential to bring 10 inches of rain through northern parts of the state this weekend and two to three feet of snow in the Sierra Nevada, said David Novak, director of the U.S. Weather Prediction Center in College Park, Maryland.

Wind gusts up to 60 miles per hour are possible across the region. Wind and storm warnings stretch from Washington to southern California, according to the weather service.

The lack of rain in California through February means there is room in reservoirs to handle the immediate runoff, which should help with flooding, said Andy Morin of the California Nevada River Forecast Center in Sacramento. “It would be a welcome increase in water supply,” he said on the call.

Central U.S.

That system will then move into the central U.S. where it will stall and bring rains throughout the region -- particularly to Arkansas, Texas and Louisiana, Novak said.

Depending on how the rain in the central U.S. falls, it could prompt another round of flooding in the Mississippi and other rivers in the region, Uccellini said. The Bonnet Carre Spillway upstream from New Orleans had to be opened in January to keep the waters from spilling into city streets.

“That is something that we have to watch,” Uccellini said. “We do have that concern. This is the area that was affected by the late Christmas and early January event.”

The second storm, forecast to arrive early next week, could push the seven-day rain totals in parts of northern California to 20 inches and across the U.S. South to more than 10 inches, according to the Weather Prediction Center.

Before it's here, it's on the Bloomberg Terminal. LEARN MORE