- Already more than 4 feet of snow across the central Sierra Nevada.
- Widespread additional 1 to 3 feet of snow expected
- Travel extremely dangerous and impossible at times.
- Bitter wind chills for much of the East coast.
- Will feel like 25 degrees below zero at times across Interior Northeast.
“A major winter storm with an active atmospheric river is inundating California with a tremendous amount of moisture,” warns the National Weather Service. Then comes accumulating snowfall for the Midwest and cold, cold, cold.
Heavy to excessive rainfall is likely from central to southern California that may produce dangerous flash flooding along with mudslides and dangerous debris flows near recent and vulnerable burn scars. A significant amount of snow is likely for the California mountains and terrain.
NWS Weather Prediction Center College Park MD
Valid Fri Jan 29 2021 – Sun Jan 31 2021
Heavy rain and flash flooding remains possible across portions of southern California tonight.
Additional heavy snow expected across the Sierra Nevada through early Friday.
Low pressure system to develop over the central Plains Saturday and bring accumulating snowfall to parts of the Midwest.
Ongoing heavy precipitation continues to unfold across central and southern California this afternoon as an atmospheric river swings through the region.
Up to 12 inches of rain has already fallen along coastal areas, with more than 4 feet of snow across the central Sierra Nevada.
Heavy rain going into tonight will shift to coastal sections of southern California where up to 3 inches of rain is expected to fall, with locally higher amounts. Flash flooding and debris flows will be possible near recent burn scars, as soil cannot retain much rain in a short amount of time. Flash Flood Watches are currently in effect.
Meanwhile, heavy snow is expected to continue through Friday morning across the central and southern Sierra Nevada. A widespread additional 1 to 3 feet of snow can be expected, making travel extremely dangerous and impossible at times.
This same system is forecast to exit the Southwest U.S. by Friday evening, with lingering snow showers remaining throughout the Great Basin and Intermountain West. Cold arctic air to the north of the system will allow for precipitation to fall as snow from eastern Nebraska to Indiana.
More wintry weather will be likely with this storm as it tracks east later in the weekend.
Elsewhere, much of the East Coast will be dealing with bitter wind chills tonight into Friday morning. Wind Chill advisories are in effect across the Interior Northeast, where it will feel like 25 degrees below zero (-31.7C) at times. Snow showers will also accompany the cold air along immediate coastal sections of New England through Friday.