FXUS66 KSTO 261933

AFDSTO



Area Forecast Discussion

National Weather Service Sacramento CA

1233 PM PDT Thu Jun 26 2025



.DISCUSSION...



.SYNOPSIS...

Seasonably warm temperatures accompanied by dry weather and 

periodically breezy onshore winds through the remainder of the 

week. A warming trend to widespread Moderate HeatRisk is then 

anticipated over the the weekend into next week. Mountain 

thunderstorm chances return early early to mid next week.



&&



.KEY MESSAGES...



* Through Friday:

 -Near to slightly above normal temperatures expected, with Delta,

  Valley, and foothills high temperatures in the 80s to 90s and

  70s to 80s in the mountains

 -Minor HeatRisk expected today with areas of Moderate HeatRisk 

  on Friday

 

* This Weekend: 

 -Warming trend into the weekend with high temperatures across the

  Delta, Valley, and foothills in the 90s to lower triple digits

  and 80s to low 90s expected at higher elevations

 -Widespread Moderate HeatRisk returns to interior NorCal for

  Saturday and Sunday

 -Probability of Valley high temperatures > 100F:

  Northern/Portions of the Central Sacramento Valley: 65-95%;

  Delta, S. Sac Valley, N. San Joaquin Valley: 10-30%

 -Less than 10% probability of a shower or thunderstorm over the

  mountains this weekend



* Early to Mid Next Week:

 -Above normal temperatures persist into next week with Moderate

  HeatRisk, although increased onshore flow brings some relief to

  the Delta vicinity Monday-Tuesday

 -Slight (10-20%) probability of thunderstorms early to mid next

  week during the afternoon and early evening hours across the

  mountains of interior NorCal



.Changes from previous forecast...

 -Decrease in mountain thunderstorm potential this weekend

 

&&



.AVIATION...

VFR conditions prevail across interior NorCal next 24 hours. 

Surface winds generally below 15 knots, with an occasional gust up

to 20 knots in the Delta and in the mountains, as onshore flow 

strengthens this evening in the Delta and drainage wind speeds 

increase in the mountains. 



&&



.STO WATCHES/WARNINGS/ADVISORIES...

None.



&&



$$

