Major Early Season Snow Event for the West

A significant pattern change is underway across the West this week. Following a period of mild and dry fall weather, a strong storm originating in the Gulf of Alaska is impacting the Pacific Northwest and will spread across the Northern Rockies on Wednesday and Thursday.

As the storm progressed southward, moderate to heavy snow fell across British Columbia and Alberta on Monday night and Tuesday. Check out the snow stake cam at Castle Mountain in Alberta on Tuesday afternoon. 

Snowfall on Wednesday and Thursday will favor the Cascades, Northern Rockies, and Northern Utah with Big Sky, Jackson Hole, Grand Targhee, and Alta/Snowbird cashing in on some of the deeper totals. Colorado will see most of its action on Friday and Saturday.

Check out our 5-Day Powder Finder:

Forecast for Wed (Oct 25) to Thu (Oct 26):

Heavy snow will spread eastward from the Cascades into the Northern Rockies and Utah, with lighter snow for the Tahoe on the southern edge of the storm track.

For more details, check out these Daily Snows from our local forecasters:

• Washington
• Oregon 
• Montana
• Utah
• Idaho
• Boise Region
• Jackson Hole 
• Tahoe

In addition to snow, cold air will filter into the Western U.S. during this period, resulting in cold temperatures for this time of year along with low snow levels.

Elsewhere, rain will overspread the Great Lakes region while the East will remain warm and dry with good trail and leaf-peeping conditions expected. 

Forecast for Fri (Oct 27) to Sat (Oct 28):

A second storm will move into the West during this period. The storm will be weaker for the Cascades and Northern Rockies with only light snow expected. However, as the storm progresses southward, it will strengthen over Colorado with moderate to locally heavy snow possible.

An early season surge of arctic air will also move into the West during this period, resulting in well-below-average temperatures for this early in the season.

Meanwhile, a storm will move across the Upper Midwest with a swath of snow developing from North Dakota into Far Northern Minnesota and Ontario. Lighter precipitation is expected across Southern Minnesota into Wisconsin, but the arrival of colder air will result in a changeover from rain to light snow.

Forecast for Sun (Oct 29) to Mon (Oct 30):

Snow will linger across Colorado into Sunday before tapering off, and the rest of the West will see dry conditions along with below-average temperatures.

The pattern will turn more active across the East as a strong cold front approaches with snow showers developing across the Great Lakes and Southeast Canada. Widespread rain can be expected in the Eastern U.S. in the warm sector of this system, but colder air looms just beyond this period. 

Outlook for Tue (Oct 31) to Sat (Nov 4):

The West will likely start out dry early on in this pattern, then an active storm track will return to the Northwest and Northern Rockies as the calendar flips to November. A much colder airmass will also take hold across the East with opportunities for snow expected across the Great Lakes and New England. 

Thanks so much for reading! Next update on Friday (October 27).

Alan Smith