Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
442 PM EDT Fri Apr 03 2020

Valid 00Z Sat Apr 04 2020 - 00Z Tue Apr 07 2020


...Western U.S....

Days 1-3...
A shortwave trough and a deepening upper low are forecast to bring
late season heavy snows to portions of the southern Cascades and
the California mountains, with heaviest amounts expected in the
Shasta region and along the Sierra.  Models show a compact
mid-to-upper level low dropping southeast and weakening as it
moves into Oregon and southern California on Saturday.  This
initial system is expected to bring periods of snow, with
potentially heavy accumulations across portions of the southern
Cascades, the coastal ranges of northwest California and the
northern Sierra on Saturday.  Heavier snowfall will follow on
Sunday and Monday as a deepening upper low dropping south over the
eastern Pacific reaches the southern Oregon and northern
California coasts Sunday morning.  As the low continues to dig
south, heavy snows developing over northern California on Sunday
will shift farther to the south into central and southern
California, with impacts extending south along the Sierra into the
Transverse Ranges.  For the three day period ending 00Z Tuesday --
heaviest totals are expected to include the Shasta region as well
as the Sierra -- where WPC PWPF indicates high probabilities for
accumulations of 2-feet or more.

Pereira