525
FXUS66 KSTO 141952
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1252 PM PDT Wed May 14 2025

.Discussion...

.Synopsis...
Drier and warmer weather persist through Friday, with
occasionally breezy winds through the end of the week. The next
weather system then looks to arrive by the weekend, bringing
mountain/foothills thunderstorm chances Saturday, followed by
gusty and drying north winds Sunday into next week. Resultant
elevated fire weather conditions are anticipated Sunday and
Monday, potentially lingering into Tuesday, throughout the Valley
due to the gusty winds and expected low relative humidity.

&&

.Key Messages...

* Today-Friday:
 -Dry weather and warm temperatures persist with areas of Minor
  HeatRisk in the Valley.
 -Occasionally breezy winds, with some north-northwest gusts in
  the northern/central Sacramento Valley Thursday evening.
 --Probability of wind gusts > 30 mph late Thursday-early Friday:
   20-50% along and west of Interstate 5.

* Saturday:
 -Weather system begins to drop southward from Pacific NW.
 -15-35% probability of isolated thunderstorms, highest chances
  across the northern Sacramento Valley and along the
  Sierra/southern Cascades and adjacent foothills from Interstate
  80 northward.
 -Slight chance of light snowfall above 6000 feet late Saturday-
  Sunday morning. Probability of snowfall > 1": 10-30% along
  Sierra/southern Cascades.
 -Temperatures cooling to near normal, with breezy winds
  throughout the day.

* Sunday - Tuesday:
 -Current ensemble trends indicate the expected weather system
  following an inside slider trajectory through the region.
 -Gusty north to east winds expected to develop Sunday and Monday
  as this system progresses, with lingering breezy winds into
  Tuesday.
 -Probability of gusts 40 mph or higher:
 --Sunday: 40-70%, highest along and west of I-5 in the Sacramento
  Valley.
 --Monday & Tuesday: 20-50% across the northern/central
  Sacramento Valley and Delta.
 -Elevated fire weather conditions expected Sunday and Monday,
  potentially lingering into Tuesday, due to the combination of
  gusty northerly winds and low relative humidity in the
  Sacramento Valley.
 -Warming trend expected early to mid next week, with areas of
  Moderate HeatRisk across the Valley.

.Changes from previous forecast...
 -Shower and thunderstorm chances shifting primarily to Interstate
  80 northward on Saturday.
 -Slight chance of light snow along Sierra/southern Cascades above
  6000 feet.
 -Elevated fire weather conditions potentially continue into
  Tuesday.
 -Areas of Moderate HeatRisk for the Valley expected Monday-
  Tuesday of next week.

&&

.AVIATION...
VFR conditions expected to prevail at TAF sites next 24 hours.
North-northwest winds remain breezy through the day, then becoming
lighter after 06z. Winds generally expected to remain 12 kts or
less, although some southwesterly gusts to 20 kts possible with
Delta breeze influence 00z - 06z.

&&

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

$$