National Weather Service Forecast for: Fullerton CA
Issued by: National Weather Service San Diego, CA
Updated: 12:04 pm PST Feb 1, 2026
 
Overnight

Overnight: Partly cloudy, with a low around 53. Calm wind.
Partly Cloudy
 Monday

Monday: Mostly sunny, with a high near 76. Calm wind becoming southwest around 5 mph in the afternoon.
Mostly Sunny
 Monday
Night
Monday Night: Mostly clear, with a low around 52. Calm wind.
Mostly Clear
 Tuesday

Tuesday: Sunny, with a high near 83. Calm wind becoming west around 5 mph in the afternoon.
Sunny
 Tuesday
Night
Tuesday Night: Clear, with a low around 56. Calm wind.
Clear
 Wednesday

Wednesday: Sunny, with a high near 89.
Sunny
 Wednesday
Night
Wednesday Night: Mostly clear, with a low around 58.
Mostly Clear
 Thursday

Thursday: Mostly sunny, with a high near 83.
Mostly Sunny
 Thursday
Night
Thursday Night: Mostly cloudy, with a low around 57.
Mostly Cloudy
Lo 53 °F Hi 76 °F Lo 52 °F Hi 83 °F Lo 56 °F Hi 89 °F Lo 58 °F Hi 83 °F Lo 57 °F

Air Quality Alert
 

Overnight
 
 Partly cloudy, with a low around 53. Calm wind.
Monday
 
 Mostly sunny, with a high near 76. Calm wind becoming southwest around 5 mph in the afternoon.
Monday Night
 
 Mostly clear, with a low around 52. Calm wind.
Tuesday
 
 Sunny, with a high near 83. Calm wind becoming west around 5 mph in the afternoon.
Tuesday Night
 
 Clear, with a low around 56. Calm wind.
Wednesday
 
 Sunny, with a high near 89.
Wednesday Night
 
 Mostly clear, with a low around 58.
Thursday
 
 Mostly sunny, with a high near 83.
Thursday Night
 
 Mostly cloudy, with a low around 57.
Friday
 
 Partly sunny, with a high near 76.
Friday Night
 
 Mostly cloudy, with a low around 54.
Saturday
 
 Mostly sunny, with a high near 76.
Saturday Night
 
 Partly cloudy, with a low around 54.
Sunday
 
 Mostly sunny, with a high near 80.

 

Forecast from NOAA-NWS for Fullerton CA.