Another atmospheric river: High rain & snow rates, strong gusts

While the northeast of the U.S. will deal with a Nor’easter, parts of central and southern California will continue to deal with excessive rainfall that causes life-threatening floods and dangerous runoff as well as heavy mountain snow. The atmospheric river will be turned on through late Wednesday afternoon across California.

The series of storms continues to move onshore on Tuesday onto California, but this system is attached to another low-pressure system by a stationary front, that will enhance the chance for periods of heavy precipitations over the Great Basin and the northern Rockies, where the low-pressure system is located.

The new storm moving onto California will drag a cold front that will sweep the Golden State on Tuesday and Wednesday and warranties plenty of rain for much of the state’s lower elevations and coast. This storm will move toward the Great Basin, keeping the risk for winter precipitation high for Oregon as well. Rains will start to ease off late Wednesday afternoon, but a few rain showers will still be possible from Los Angeles to San Diego.

Once again, the San Joaquin Valley could receive 5 to 7 inches of rain through Thursday morning, mostly falling from Tuesday to Wednesday morning.

For Southern California, 2 to 5 inches of rain will be possible over the Santa Barbara Coast with up to 1 inch per hour rain rates at some points through late Wednesday afternoon. This rainfall could cause mudslides or rockslides, river flooding, and debris flows, especially over recent burn scars.

The Southern California mountains and foothills could receive 4 to 8 inches of rain, especially for the southwest-facing slopes. Elevations above 8,000 feet over SoCal, will get little snow at best.

Across the Sierra, Nevada impacts will be widespread. There is a winter storm warning that will drop heavy snowfall at times with snowfall rates between 2 to 3 inches per hour. Road closures are imminent as traveling will be difficult to impossible across some locations.

Winds will be strong for the mountains and the Antelope Valley, with isolated gusts up to 60 mph. Power outages are likely as the heavy rain and strong winds will put pressure on powerlines and trees that could fall over powerlines. See how the winds affect California in our WindRadar