Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
512 AM EDT Tue Mar 16 2021

Valid 12Z Tue Mar 16 2021 - 12Z Fri Mar 19 2021

...Colorado and New Mexico to southeastern Kansas and the
Oklahoma/Texas Panhandles...
Day 1-2...
A vigorous upper low dropping southeast into Arizona this morning
is forecast to move east into New Mexico -- bringing mountain
snows into Colorado and New Mexico later today.  There remains a
pretty good signal for locally heavy snows developing, especially
as the low begins to move east of the mountains into the High
Plains late Tuesday into early Wednesday.   Strong northeasterly
flow along the northwest side of the low, along with favorable
forcing aloft, will likely support a period of heavy snow along
and east of the Sangre de Cristo Mountains in southeastern
Colorado and northeastern New Mexico.  WPC PWPF indicates snow
accumulations of 4-inches or more are likely from the mountains
eastward along the Colorado-New Mexico border, with higher totals
likely in the mountains.  As the low continues farther east, heavy
precipitation may support rain changing to snow within the
system's deformation band -- producing at least a few inches of
snow across portions of southeastern Kansas and the northern
Panhandle region on Wednesday.

...Western U.S....
Day 3...
A frontal band associated with an upper low/trough approaching the
Pacific Northwest will bring the next round of mountain snows into
the western U.S. beginning Thursday and continuing into early
Friday.  The areas most likely to see significant accumulations
through early Friday include the Olympics, the southern Cascades
and northern Sierra.

For Days 1-3, the probability of significant icing (0.25-inch or
greater) is less than 10 percent.

Pereira