000
FXUS66 KSTO 292331
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
331 PM PST Tue Nov 29 2022

.SYNOPSIS...
Cool and dry weather continues into Wednesday with near freezing
minimum temperatures in the Central Valley. A pair of winter
storms are expected for late week, the first arriving Wednesday
and continuing into early Friday followed by the second Friday
night through Sunday. Cool and dry weather returns next week.

&&

.DISCUSSION...
Today has been a sunny, dry and cooler day. Afternoon
temperatures are about 3 to 6 degrees cooler than yesterday. Cold
overnight temperatures are expected again tonight with minimums
dropping back down into the upper 20s to lower 30s in the Central
Valley. Some high clouds ahead of an approaching storms system
look to spread over the northern Sacramento Valley area by
sunrise Wednesday and these may limit the cooling of that area
and keep temperatures up a bit.

Confidence is high sith strong ensmble consistenct that a cold
system origination from western Canada will bring widespread rain
and heavy mountain snow Wednesday night, with up to 1 to 3 feet of
snow expected Wednesday night into early Friday. The Winter Storm
Watch has been upgraded to a Winter Storm Warning. Snow will
start in the mountains of Shasta County Wednesday afternoon, and
then spread southward through the evening, with snow levels 2500
feet to start then dropping to around a 1000 feet by early Friday.
Heaviest snow is forecast for Thursday, where heavy rates of 2 to
3 inches an hour are possible, especially over the northern
Sierra, with lighter snow by early Friday. Heavy snow is expected
above 3000 feet for the Sierra and the mountains of western
Plumas County and Lassen National Park, but a dusting to couple
inches of snow is possible above 2500 feet.

In addition to snow, gusty winds are projected with the coming
storm. Gusts to 55 to 65 mph could bring blowing snow and whiteout
conditions at times over the higher elevations. In the Valley,
winds could gust to 25 to 40 mph as a cold front pushes through
during the day Thursday. Make sure decorations and outdoor
furniture are secured!

Rain totals through Friday are still expected to reach 1 to 2
inches in the Valley, 1 1/2 to 3 inches in the foothills. The lack
of convection and the cold nature of this storm with lower snow
levels should limit the potential for burn scar impacts.

&&
.EXTENDED DISCUSSION (Saturday THROUGH Tuesday)...
A second storm is expected for late Friday through the weekend.
Ensembles suggest this storm should be similar to the first, with
another 1 to 3 feet of mountain snow expected. This system has
precipitation more spread out, so snow will likely not be as
intense. This storm will likely cause significant weekend travel
disruptions in the mountains. The heaviest snow over the northern
Sierra will be Saturday afternoon through Saturday night. Snow
levels will start low (around 1000-2000 feer) then gradually rise
to 3500-4000 feet.

This storm be a colder system, so snow could extend further down,
potentially into the northern Sacramento Valley early Saturday.
Confidence in this is not high and current amounts are projected
to be light. Another difference from Storm #1 is that the wind
will not be as strong.

Drier weather returns early next week with potential for more
near-freezing temperatures in the Central Valley beginning Monday
morning and continuing into at least mid-week.
&&

.AVIATION...
VFR conditions through Wednesday morning with the exception of
local MVFR visibility for BR possible between 12Z-16Z Wednesday in
the northern San Joaquin Valley. A weather system will spread
precipitation from north to south mainly after 00z Thu with MVFR
conditions in the Valley and IFR conditions over the mountains.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 4 PM Wednesday to 10 PM PST Thursday
for Burney Basin / Eastern Shasta County-Mountains Southwestern
Shasta County to Western Colusa County-Shasta Lake Area /
Northern Shasta County-West Slope Northern Sierra Nevada-Western
Plumas County/Lassen Park.

&&

$$