National Weather Service Forecast for: 3 Miles N Saint Helena CA
Issued by: National Weather Service San Francisco Bay Area/Monterey, CA
Updated: 1:26 am PDT Aug 20, 2026
 
Overnight

Overnight: Patchy fog after 3am. Otherwise, mostly cloudy, with a low around 55. Calm wind.
Patchy Fog

 Thursday

Thursday: Patchy fog before 9am. Otherwise, partly sunny, with a high near 87. Light south wind.
Patchy Fog
then Partly
Sunny
 Thursday
Night
Thursday Night: Mostly cloudy, with a low around 55. Calm wind.
Mostly Cloudy

 Friday

Friday: Partly sunny, with a high near 85. Calm wind becoming west southwest around 5 mph in the afternoon.
Partly Sunny

 Friday
Night
Friday Night: Patchy fog after 2am. Otherwise, mostly clear, with a low around 53. West southwest wind around 5 mph becoming calm in the evening.
Mostly Clear
then Patchy
Fog
 Saturday

Saturday: Areas of fog before 9am. Otherwise, sunny, with a high near 86.
Areas Fog
then Sunny
 Saturday
Night
Saturday Night: Mostly clear, with a low around 54.
Mostly Clear

 Sunday

Sunday: Mostly sunny, with a high near 87.
Mostly Sunny

 Sunday
Night
Sunday Night: Partly cloudy, with a low around 54.
Partly Cloudy
Lo 55 °F Hi 87 °F Lo 55 °F Hi 85 °F Lo 53 °F Hi 86 °F Lo 54 °F Hi 87 °F Lo 54 °F

 

Overnight
 
 Patchy fog after 3am. Otherwise, mostly cloudy, with a low around 55. Calm wind.
Thursday
 
 Patchy fog before 9am. Otherwise, partly sunny, with a high near 87. Light south wind.
Thursday Night
 
 Mostly cloudy, with a low around 55. Calm wind.
Friday
 
 Partly sunny, with a high near 85. Calm wind becoming west southwest around 5 mph in the afternoon.
Friday Night
 
 Patchy fog after 2am. Otherwise, mostly clear, with a low around 53. West southwest wind around 5 mph becoming calm in the evening.
Saturday
 
 Areas of fog before 9am. Otherwise, sunny, with a high near 86.
Saturday Night
 
 Mostly clear, with a low around 54.
Sunday
 
 Mostly sunny, with a high near 87.
Sunday Night
 
 Partly cloudy, with a low around 54.
Monday
 
 Patchy fog before 9am. Otherwise, mostly sunny, with a high near 84.
Monday Night
 
 Patchy fog. Otherwise, partly cloudy, with a low around 53.
Tuesday
 
 Areas of fog. Otherwise, mostly sunny, with a high near 85.
Tuesday Night
 
 Patchy fog. Otherwise, partly cloudy, with a low around 54.
Wednesday
 
 Patchy fog. Otherwise, mostly sunny, with a high near 87.

 

Forecast from NOAA-NWS for 3 Miles N Saint Helena CA.