229
FXUS66 KSTO 231036
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
236 AM PST Sun Feb 23 2025

.SYNOPSIS...
A weak system will bring light showers to the Coast Range, Shasta
county, the southern Cascades and adjacent foothills today and
then an even weaker system on Monday. Breezy southerly winds are
expected on Monday. Dry weather and well above normal
temperatures then continue next week.

&&

.DISCUSSION...
Upper level ridge over NorCal will flatten today, as weak system
moves through the Pacific Northwest. This will allow moisture to
move over the top of ridge into far NorCal, bringing light
showers to the Coast Range, Shasta County and the southern
Cascades through this afternoon. Rainfall amounts over Shasta
County will generally be around 0.25 inches or less, with higher
amounts over the mountains where up to 0.50-0.75 inches are
possible. Dry weather is expected over most of the Sacramento
Valley, the northern Sierra, and the northern San Joaquin Valley.
This is a warm system with high snow levels above 8000 feet so no
mountain snow impacts are expected. Temperatures will continue to
be slightly above normal this afternoon, with Valley highs
ranging from the mid 60s to low 70s.

Another system will approach the Pacific Northwest on Monday, but
moisture will be limited over NorCal with amounts less than 0.25
over the Coast Range, Shasta County and the southern Cascades.
Very little rainfall is expected south of these areas and high
snow levels will prevent any snowfall. Breezy southerly winds
are also expected for Monday, with gusts 15 to 35 mph in the
northern/central Sacramento Valley and adjacent foothills, and
gusts up to 40-45 mph over the northern Sierra and southern
Cascades. Upper level ridge will reamplify over Norcal Tuesday and
for much of the week with above normal high temperatures in the
70s over much of the Valley.

&&

.EXTENDED DISCUSSION (Thursday THROUGH Sunday)...
Dry weather and above normal temperatures are expected mid to
late week as ensembles and clusters indicate ridging dominating
the pattern. Highs will range from 5 to 15 degrees above
climatology across the area, with Friday currently forecast to be
the warmest day of the week. In addition, the NBM shows a 10-35%
probability of temperatures exceeding 80 degrees F across portions
of the northern/central Sacramento Valley on Friday. Ensembles
show a weather system dropping into SoCal late week, but interior
NorCal appears to remain dry. Cluster and ensemble guidance are
then hinting at a possible trough later Saturday night and Sunday
that may bring light precipitation to the area. Specific details
are uncertain. Additionally, the Climate Prediction Center`s 8 to
14 extended outlook favors below normal temperatures and above
normal precipitation for interior NorCal for the first week of
March.

&&

.AVIATION...
Areas of brief MVFR conditions in showers across portions of the
northern Sacramento Valley, Coast Range and southern Cascades
until 00z Monday, and again after 18z Monday. Elsewhere, VFR
conditions are expected with surface winds generally under 12 kts.
Breezy southerly winds after 18z Monday, with gusts up to 20-30
kts across portions of the northern/central Sacramento Valley, and
up to 35 kts over the mountains.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$