Grass Valley, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

089
FXUS66 KSTO 052033
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
133 PM PDT Thu Jun 5 2025

.DISCUSSION...

.SYNOPSIS...
Warm and dry weather continues today, with a warm-up expected over
the weekend, with likely triple digit temperatures and Major
HeatRisk in parts of the northern Sacramento Valley. Periodically
breezy winds continuing into next week. Daily afternoon/evening
mountain thunderstorm chances (10-15%) will continue today and
through the weekend over the High Sierra.

&&

.KEY MESSAGES...

* Today-Tuesday:

 -Slightly cooler temperatures today, before high temperatures
  follow a warming trend Friday and into early next week with
  Moderate HeatRisk and some areas of Major HeatRisk

 --Probability of Valley High Temperatures > 95F:
  ---Northern/Central Sacramento Valley: 75-100%
  ---Delta, S. Sacramento Valley, N. San Joaquin Valley: 40-80%

 --Probability of Valley High Temperatures > 100F:
  ---Northern/Central Sacramento Valley: 40-70%, Saturday-Monday

 -Chances for isolated afternoon/early evening mountain showers
  and thunderstorms:
--Today-Saturday: 15-25%, South of US 50 along the Sierra Crest.
--Sunday-Monday: 10-20%, Along the Sierra Crest

.CHANGES FROM PREVIOUS FORECAST...

 -Probability for temperatures over 100F have increased slightly
  in the northern Sacramento Valley

&&

.AVIATION...
VFR conditions prevail over interior NorCal next 24 hours.
Surface winds generally below 12 kts, except in the vicinity of
the Delta where surface winds could get up to 25 kts between 22Z
Thursday and 06Z Friday. Additionally, there is a 15-25% chance of
isolated showers or thunderstorms over the Sierra south of US 50
until and 03Z Friday.

&&

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

&&

$$