341
FXUS66 KSTO 042050
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
150 PM PDT Thu Jun 4 2026



.KEY MESSAGES...

 -Very warm conditions continue through Friday with Widespread
  moderate HeatRisk with. Cooling to near normal temperatures
  starts Saturday, dropping below normal early next week.

 -Dry weather except for chances of showers Monday and Tuesday,
  with the potential beginning to increase.

 -Breezy afternoon and evening winds through Sunday with low
  humidity bringing a few areas of elevated fire conditions.

&&

.DISCUSSION...

...Main update to the forecast is increasing chances of light
rain showers Monday and Tuesday, now extending into the
Sacramento Valley and Delta(15-25% chance)...

...Today and Friday...
Temperature forecast still on track with highs 10-15 degrees above
normal, generally in the mid to upper 90s for . NBM probabilities
in the Valley show a 20-30% chance of temperatures reaching 100
degrees or greater. Winds aloft will be from the west northwest as
a weather system drops south out of the Gulf of Alaska, which
will bring delta breezes and breezy west to northwest winds at
times.

...Saturday and Sunday...
The trough from the Gulf of Alaska(generally less then
30%) look to be confined to the will knock down the ridge over
the weekend, with notably cooler, near normal high temperatures.
This means mainly mid to upper 80s for the Valley, Delta and
lower foothills. Relative humidities remain low in the Valley and
combined with the gusty northwest winds will bring a few hours of
elevated fire concerns in the north Sacramento Valley through
Sunday. This system will be dry, with wind and and cooler
temperatures the main effects.

A secondary trough will move in behind the first for early next
week. This system has more moisture, and ensembles have been
trending deeper and wetter with it. Chances have increased for the
foothills and mountains, and are now extending into the Sacramento
Valley. Stay tuned as more details become know about this system.

&&

.AVIATION...
VFR conditions with clear skies at TAF sites over the next 24
hours. Northwest surface winds sustained 10 to 15 kts with gusts
15 to 20 kts in the northern San Joaquin Valley through early
Friday morning (10Z). In the Delta vicinity, west winds sustained
10 to 15 kts with gusts to 20 kts through 12Z Friday. Northwest
winds decreasing for the Sacramento Valley generally 10 kts or
less this evening and overnight, increasing after 16Z Friday to 10
kts with gusts to 20 kts for the northern Sacramento Valley.

&&

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

$$