National Weather Service Forecast for: Guerneville CA
Issued by: National Weather Service San Francisco Bay Area/Monterey, CA
Updated: 1:26 am PDT Jun 22, 2026
 
Overnight

Overnight: Patchy fog. Otherwise, partly cloudy, with a low around 52. Calm wind.
Patchy Fog

 Monday

Monday: Partly sunny, then gradually becoming sunny, with a high near 80. Calm wind becoming south southwest around 6 mph in the afternoon.
Becoming
Sunny
 Monday
Night
Monday Night: Patchy fog after midnight. Otherwise, increasing clouds, with a low around 52. Calm wind.
Mostly Clear
then Patchy
Fog
 Tuesday

Tuesday: Mostly cloudy, then gradually becoming sunny, with a high near 81. Calm wind becoming south southwest around 6 mph in the afternoon.
Decreasing
Clouds
 Tuesday
Night
Tuesday Night: Patchy fog after midnight. Otherwise, partly cloudy, with a low around 52. Light and variable wind.
Mostly Clear
then Patchy
Fog
 Wednesday

Wednesday: Patchy fog before 8am. Otherwise, mostly sunny, with a high near 82.
Patchy Fog
then Sunny
 Wednesday
Night
Wednesday Night: Partly cloudy, with a low around 54.
Partly Cloudy

 Thursday

Thursday: Sunny, with a high near 86.
Sunny

 Thursday
Night
Thursday Night: Mostly clear, with a low around 56.
Mostly Clear
Lo 52 °F Hi 80 °F Lo 52 °F Hi 81 °F Lo 52 °F Hi 82 °F Lo 54 °F Hi 86 °F Lo 56 °F

 

Overnight
 
 Patchy fog. Otherwise, partly cloudy, with a low around 52. Calm wind.
Monday
 
 Partly sunny, then gradually becoming sunny, with a high near 80. Calm wind becoming south southwest around 6 mph in the afternoon.
Monday Night
 
 Patchy fog after midnight. Otherwise, increasing clouds, with a low around 52. Calm wind.
Tuesday
 
 Mostly cloudy, then gradually becoming sunny, with a high near 81. Calm wind becoming south southwest around 6 mph in the afternoon.
Tuesday Night
 
 Patchy fog after midnight. Otherwise, partly cloudy, with a low around 52. Light and variable wind.
Wednesday
 
 Patchy fog before 8am. Otherwise, mostly sunny, with a high near 82.
Wednesday Night
 
 Partly cloudy, with a low around 54.
Thursday
 
 Sunny, with a high near 86.
Thursday Night
 
 Mostly clear, with a low around 56.
Friday
 
 Sunny, with a high near 81.
Friday Night
 
 Mostly clear, with a low around 56.
Saturday
 
 Sunny, with a high near 81.
Saturday Night
 
 Mostly clear, with a low around 54.
Sunday
 
 Sunny, with a high near 85.

 

Forecast from NOAA-NWS for Guerneville CA.