490
FXUS66 KSTO 301907
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1207 PM PDT Sat May 30 2026

.KEY MESSAGES...

 -Slight chance for mountain showers or an isolated t-storm over
  the higher elevations of the southern Cascades, Shasta County
  mountains and Burney Basin this afternoon

 -Drier and warmer weather Sunday with period of increased
  northerly flow in the morning

 -Dry and warming weather next week, with areas of Moderate
  HeatRisk, low humidity and periodically breezy onshore flow

&&

.DISCUSSION...

...Today through Sunday...
Current GOES-West satellite imagery shows cumulus clouds across
much of interior northern California on this Saturday afternoon.
Temperatures are trending approximately 10 to 20 degrees warmer
than this time yesterday afternoon. Forecast highs will be in the
70s to 80s today in the Valley and foothills, and 50s to 70s in
the mountians. The warming trend will continue on Sunday with
highs in the 60s to upper 80s across the forecast area. Isolated
showers or a thunderstorm will be possible this afternoon over the
Shasta County mountains, Burney Basin and southern Cascades (10
to 15 percent chance), with dry conditions elsewhere. A brief
period of increased northerly flow will develop Sunday morning,
with gusts of 15 to 20 mph mainly in the northern and central
Sacramento Valley. Winds are forecast to peak in the early to mid
morning hours before decreasing through the day.

...Monday through Friday...
Dry weather and above normal temperatures can be expected through
at least the middle of the week, along with areas of Moderate
HeatRisk in the Valley and onshore flow. Forecast high
temperatures are currently projected to be in the upper 80s to low
90s in the Valley. Dry conditions and low afternoon humidity is
anticipated for much of next week, in the mid teens to mid 20s.
Periods of onshore breeziness will bring late day and overnight
cooling to the Delta and adjacent Valley locations, keeping
HeatRisk in the Minor category. A weak trough looks to cross the
Pacific Northwest on Wednesday, and there is potential for some
increase northerly flow behind it on Thursday. Towards the end of
the week, ensembles are then showing an upper level trough
dropping down and moving across the region next weekend. While
there is still some uncertainty with this, it does look like a
cooling trend and increased onshore flow is then favored for the
end of next week into the following weekend. There is potential
for some periods of elevated fire weather conditions in breezy
winds and low humidity alignment next week with drying of fuels.
Be sure to stay up to date with the latest forecasts at
weather.gov!

&&

.AVIATION...
VFR conditions at TAF sites over the next 24 hours. Isolated
shower or thunderstorms (10-15% chance) from 18Z-03Z over Shasta
County mountains, Burney Basin and southern Cascades bringing
local MVFR/IFR conditions. Sustained surface winds generally less
than 12 kts in the Valley, except the Delta with southwest gusts
to 20-25 kts through 06Z Sunday. Northerly flow will then increase
bringing a brief periods of 15-20 kt gusts mainly to the
north/central Sacramento Valley through 18Z and then decreasing.

&&

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

&&

$$