National Weather Service Forecast for: Sunnyvale CA
Issued by: National Weather Service San Francisco Bay Area/Monterey, CA
Updated: 1:40 am PST Dec 5, 2025
 
Overnight

Overnight: Mostly clear, with a low around 39. West northwest wind around 5 mph.
Mostly Clear

 Friday

Friday: Sunny, with a high near 63. North northwest wind around 7 mph.
Sunny

 Friday
Night
Friday Night: Patchy fog after 5am. Otherwise, increasing clouds, with a low around 44. West northwest wind around 5 mph becoming calm in the evening.
Mostly Clear
then Patchy
Fog
 Saturday

Saturday: Mostly cloudy through mid morning, then gradual clearing, with a high near 63. Northwest wind 3 to 8 mph.
Becoming
Sunny
 Saturday
Night
Saturday Night: Mostly clear, with a low around 45. West northwest wind 6 to 8 mph.
Mostly Clear

 Sunday

Sunday: Mostly sunny, with a high near 65.
Mostly Sunny

 Sunday
Night
Sunday Night: Partly cloudy, with a low around 46.
Partly Cloudy

 Monday

Monday: Patchy fog before 9am. Otherwise, mostly sunny, with a high near 65.
Patchy Fog
then Sunny
 Monday
Night
Monday Night: Mostly clear, with a low around 47.
Mostly Clear
Lo 39 °F Hi 63 °F Lo 44 °F Hi 63 °F Lo 45 °F Hi 65 °F Lo 46 °F Hi 65 °F Lo 47 °F

 

Overnight
 
 Mostly clear, with a low around 39. West northwest wind around 5 mph.
Friday
 
 Sunny, with a high near 63. North northwest wind around 7 mph.
Friday Night
 
 Patchy fog after 5am. Otherwise, increasing clouds, with a low around 44. West northwest wind around 5 mph becoming calm in the evening.
Saturday
 
 Mostly cloudy through mid morning, then gradual clearing, with a high near 63. Northwest wind 3 to 8 mph.
Saturday Night
 
 Mostly clear, with a low around 45. West northwest wind 6 to 8 mph.
Sunday
 
 Mostly sunny, with a high near 65.
Sunday Night
 
 Partly cloudy, with a low around 46.
Monday
 
 Patchy fog before 9am. Otherwise, mostly sunny, with a high near 65.
Monday Night
 
 Mostly clear, with a low around 47.
Tuesday
 
 Mostly sunny, with a high near 66.
Tuesday Night
 
 Partly cloudy, with a low around 49.
Wednesday
 
 Mostly sunny, with a high near 67.
Wednesday Night
 
 Mostly clear, with a low around 49.
Thursday
 
 Patchy fog. Otherwise, sunny, with a high near 68.

 

Forecast from NOAA-NWS for Sunnyvale CA.