Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
418 PM EDT Sun Oct 13 2019

Valid 00Z Mon Oct 14 2019 - 00Z Thu Oct 17 2019

Days 1-3...

...Western Montana...
An open trough crosses the southern Canadian Rockies tonight with
Pacific moisture over upslope portions of windward terrain in
westerly flow, aiding potential moderate snow in northwest MT
Sunday night to early Monday. Snow elevations will be around
5000ft, so higher passes should see some impact. With the trough
moving onto the northern Plains and drier moving in aloft, snow
should quickly taper Monday afternoon.

...Northern Great Lakes...
The center of the now very occluded low that caused the blizzard
on a northern Plains a few days ago lifts northeast from Lake
Superior tonight. Patchy precipitation in the cyclonic flow will
allow snow with localized amounts above the snow elevation of
around 1000ft into Monday morning over the Arrowhead of MN and
northern WI/MI.

...Pacific Northwest...
At atmospheric river is directed into the Pac NW Tuesday night.
The tropically sourced moisture will have a rather high snow
level, above 8000ft limiting heavy snow to the highest Cascade
peaks on Day 3.

The probability of significant icing is less than 10 percent Days
1-3.
The probability of heavy snow is less than 10 percent Days 1-2.

Jackson