Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
309 AM EDT Fri May 10 2019

Valid 12Z Fri May 10 2019 - 12Z Mon May 13 2019


...Western U.S....

A cutoff low retrograding southwest across California will
reinforce southwesterly flow across the Four Corners region into
western Colorado - drawing mid level energy and deeper moisture
into the region.  This will support snow showers and the potential
for additional heavy accumulations for portions of southwestern
Colorado - especially for the San Juan Mountains above 10,000 ft,
where WPC guidance is indicating a Slight Risk for additional
amounts of a foot or more through 12Z Saturday.

Meanwhile farther west, snow showers developing near the upper low
may produce some significant accumulations along the central to
southern Sierra, with WPC guidance showing a Slight Risk for
accumulations of 8-inches or more for areas above 10,000 ft
through 12Z Saturday. 

The probability of significant icing is less than 10 percent.

Pereira