A new storm system is expected to bring rain and mountain snow across the western United States over Halloween weekend, with California and Colorado emerging as two areas to watch.
The latest OpenSnow forecast shows the storm pattern shifting south after earlier snowfall in Washington, Idaho, and Montana. By Saturday, October 31, the Sierra Nevada and Colorado’s San Juan Mountains could see additional accumulation, although warmer temperatures will keep much of the precipitation falling as rain at lower elevations.
Related: New Winter Storm Could Dump 14 Inches of Snow Across Western US Before Halloween
California Faces a Halloween Weather Shift
According to OpenSnow, another Pacific storm will reach Southern California during Halloween weekend, spreading moisture into the Southwest and eventually the Rockies.
Forecasters expect “heavy precipitation” across parts of the Southwest, with snow “mostly confined to the higher-elevation ski terrain of the Sierra and the Rockies.”
The National Weather Service in Reno also anticipates cooler, unsettled conditions, with weekend snow levels generally above 6,500 feet.
That elevation difference matters for travelers. Mountain passes could experience winter conditions while nearby valleys receive rain.
Related: Farmers’ Almanac Reveals Where Skiers Could Find the Most Snow This Winter
Colorado Mountains Could See Significant Snow
Colorado’s San Juan Mountains are another area worth watching as the storm track shifts inland.
OpenSnow identifies the San Juans as a region that could receive “significant snow totals this weekend,” even as relatively high snow levels complicate the outlook elsewhere.
The broader forecast calls for “rain and snow showers” across California and the Interior West on Friday, followed by additional precipitation Saturday and Sunday.
For skiers, the developing pattern offers another opportunity for early-season accumulation. However, fresh snowfall does not guarantee that resorts will open additional terrain.
Related: New Forecast Shows US States Where Another Snow Storm Could Hit This Week
What Happens After Halloween?
The unsettled pattern may extend into early November, with another opportunity for mountain snowfall as colder air moves through.
OpenSnow expects “snow levels should eventually drop later on Sunday as a cold front moves through,” potentially allowing snow to reach somewhat lower elevations.
Travelers heading into the Sierra Nevada or Southern Rockies should check updated local forecasts and road conditions before departing. The biggest snowfall opportunities remain concentrated in mountain terrain, not major population centers.
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