National Weather Service Forecast for: Saint Helena CA
Issued by: National Weather Service San Francisco Bay Area/Monterey, CA
Updated: 11:27 am PDT Oct 6, 2026
 
This
Afternoon
This Afternoon: Sunny and hot, with a high near 100. Calm wind becoming west around 5 mph.
Hot

 Tonight

Tonight: Mostly clear, with a low around 58. Calm wind.
Mostly Clear

 Wednesday

Wednesday: Sunny and hot, with a high near 99. Light and variable wind.
Hot

 Wednesday
Night
Wednesday Night: Mostly clear, with a low around 56. Calm wind.
Mostly Clear

 Thursday

Thursday: Sunny and hot, with a high near 99. Calm wind.
Hot

 Thursday
Night
Thursday Night: Mostly clear, with a low around 55.
Mostly Clear

 Friday

Friday: Sunny, with a high near 91.
Sunny

 Friday
Night
Friday Night: Patchy fog after 3am. Otherwise, mostly clear, with a low around 49.
Mostly Clear
then Patchy
Fog
 Saturday

Saturday: Patchy fog before 10am. Otherwise, mostly sunny, with a high near 77.
Patchy Fog
then Sunny
Hi 100 °F Lo 58 °F Hi 99 °F Lo 56 °F Hi 99 °F Lo 55 °F Hi 91 °F Lo 49 °F Hi 77 °F

Heat Advisory
Coastal Flood Advisory
 

This Afternoon
 
 Sunny and hot, with a high near 100. Calm wind becoming west around 5 mph.
Tonight
 
 Mostly clear, with a low around 58. Calm wind.
Wednesday
 
 Sunny and hot, with a high near 99. Light and variable wind.
Wednesday Night
 
 Mostly clear, with a low around 56. Calm wind.
Thursday
 
 Sunny and hot, with a high near 99. Calm wind.
Thursday Night
 
 Mostly clear, with a low around 55.
Friday
 
 Sunny, with a high near 91.
Friday Night
 
 Patchy fog after 3am. Otherwise, mostly clear, with a low around 49.
Saturday
 
 Patchy fog before 10am. Otherwise, mostly sunny, with a high near 77.
Saturday Night
 
 Mostly clear, with a low around 46.
Sunday
 
 Sunny, with a high near 74.
Sunday Night
 
 Mostly clear, with a low around 48.
Columbus Day
 
 Sunny, with a high near 75.

 

Forecast from NOAA-NWS for Saint Helena CA.