429
FXUS66 KSTO 041923
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1223 PM PDT Wed Jun 4 2025



.Discussion...

.Synopsis...
Elevated fire weather conditions are expected today for the
Sacramento Valley due to breezy north winds and low humidity,
primarily in the central and northern portions. Winds will
gradually weaken through the afternoon hours. Daily
afternoon/evening mountain shower and thunderstorm chances
(15-25%) will continue today through the weekend over the high
Sierra. Otherwise, dry and warm weather is expected elsewhere
with periodically breezy winds and evening Delta breeze influence.
A warming trend kicks in on Friday and will continue into next
week.

&&

.Key Messages...

* Today
 -Elevated fire weather conditions will persist alongside gusty
  northerly winds and low humidity through the early afternoon,
  primarily across the northern and central Sacramento Vally.
--Winds will gradually weaken through the early afternoon hours.

 -15 to 25% chance of isolated showers or thunderstorms south of
  US 50, over the high Sierra today during the afternoon and
  evening hours.

* Thursday-Tuesday:

 -Slightly cooler temperatures on Thursday, before high
  temperatures follow a warming trend Friday and into early next
  week with more widespread Moderate HeatRisk.

 --Probability of Valley high temperatures > 95F:
 ---Friday-Monday:
  ----Northern/Central Sacramento Valley: 60-90%
  ----Delta, S. Sacramento Valley, N. San Joaquin Valley: 20-40%

 --Probability of Valley high temperatures > 100F:
 ---Saturday-Monday:
  ----Northern/Central Sacramento Valley: 30-60%

 -Chances for isolated afternoon/early evening mountain showers
  and thunderstorms:
--Thursday-Friday: 15-25%, south of US 50 along the Sierra crest.
--Saturday-Monday: 10-20%, along the Sierra crest

.Changes from previous forecast...
 -Thunderstorm chances have increased for this week and over the
  weekend over the high Sierra.


&&


.AVIATION...
VFR conditions prevail over interior NorCal next 24 hours.
Surface winds around 10-20 kts, with gusts 20-30 kts over the
western portions of the Northern and Central Sacramento Valley and
higher terrain of the Sierra. Winds will begin to taper off
around 00Z Thursday. Westerly winds through the Delta will gust 15
to 25 kts until around 12Z Thursday. Additionally, there is a
15-25% chance of isolated showers or thunderstorms over the Sierra
south of US 50 between 23 and 06Z.

&&

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

$$