Atmospheric Rivers Pound US West Coast, Raising Bomb Cyclone Threat Ahead Of Christmas

Powerful atmospheric rivers continue to hammer Washington and Northern California, extending into Central California, dumping inches of rain, with some low-elevation areas seeing double-digit totals, while higher elevations are getting buried under heavy snowfall.

Here is this week’s forecast via The Weather Channel:

Atmospheric rivers continue to soak the West, bringing heavy rainfall, gusty winds and mountain snowfall. The latest event is ramping up for Northern and Central California this weekend and is expected to last into the week. Flood watches are in effect through the next several days, where widespread rainfall of 5 to 8 inches is possible through Thursday and isolated totals could near a foot. Cities like Sacramento, Los Angeles and San Francisco could see a month’s worth of rainfall this upcoming week. Mountain snowfall is also possible across the Cascades and the Sierra Nevada.

US Stormwatch founder Colin McCarthy warned that a bomb cyclone could form off the coast of California on Christmas Eve…

A bomb cyclone is likely to develop off the coast of California Christmas Eve that could bring a severe windstorm to Northern California. High Wind Watches have just been issued for the entire Bay Area for wind gusts up to 60 mph, but if more agressive model forecasts pan out wouldn’t be shocked to see 70+ mph in the higher terrain and along the coastline. A very strong cold front with potentially embedded severe thunderstorms will also come ashore late Tuesday night/early Wednesday morning in Central/Northern California that could mix very intense 60+ mph wind gusts to the surface. Given strong wind shear, can also not rule out a tornado or two.

A bomb cyclone is likely to develop off the coast of California Christmas Eve that could bring a severe windstorm to Northern California.

High Wind Watches have just been issued for the entire Bay Area for wind gusts up to 60 mph, but if more agressive model forecasts pan out… pic.twitter.com/DWnvkt8KbG

— Colin McCarthy (@US_Stormwatch) December 22, 2025

Meteorologist Brady Harris published a forecast that showed parts of the Nevada Mountain Range this week could receive “more than 8 FEET!”

⚠️ A LUDICROUS amount of Snow is likely in the Sierra Nevada Mountain Range this week. Higher elevations could see OVER 100 INCHES of Snow. That’s… more than 8 FEET ❄️

Multiple waves of Heavy Snow will fall as a PARADE OF STORMS slams California , one after another. Storm 1⃣… pic.twitter.com/eAsmTNe4XO

— Brady Harris (@StormCat5_) December 22, 2025

“So far we haven’t had much snow in the Sierra, but that is about to change,” legendary meteorologist Jim Cantore said.

A long week of HEAVY RAIN and HEAVY MOUNTAIN SNOW for California. The whole state gets it too. Late tomorrow the snow levels begin to drop and those watches will become warnings for 5500 feet on up as a series of high end AR’s (atmospheric river) punches in.

So far we haven’t… pic.twitter.com/ThCZTqVVlh

— Jim Cantore (@JimCantore) December 22, 2025

Cantore noted for the rest of the Lower 48 this week…

Meanwhile anomalous warmth dominates a most of the USA till New Year’s Eve Eve as warm ridge builds. Any travel headaches will be restricted to the northern states east of the Rockies in addition to the aforementioned CA issues. Ski Country in New England stays mostly… pic.twitter.com/hDXYieMK2b

— Jim Cantore (@JimCantore) December 22, 2025

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• Shorts Weather For Santa!

Despite warmer weather trends, meteorologist Mark Margavage warned of winter storm threats for the Northeast this week.

Woah that escalated quickly…
the forecasts that were predicting a “Christmas Torch” are going up in flames.
“December to Remember” is back in the cards!
All aboard the snow train!❄️🚂 Choo Choo!#wxtwitter #wxX #PAwx #NYwx #NJwx pic.twitter.com/hwX0uJVIJv

— Mark Margavage (@MeteoMark) December 22, 2025

A December to remember? From polar vortex outbreaks to unseasonably warm weather, Mother Nature appears unpredictable.