National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

FW0063 Fullerton CSU (F0063)

Lat: 33.8805°NLon: 117.88417°WElev: 243.01ft.

NA

87°F

31°C

Humidity 56%
Wind Speed WNW 5 MPH
Barometer 29.88 in (1011.85 mb)
Dewpoint 69°F (21°C)
Visibility NA
Heat Index92°F (33°C)
Last update 26 Aug 06:53 PM PDT
Extended Forecast for

Fullerton CA

Extreme Heat Warning August 26, 07:11pm until August 28, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning August 26, 07:11pm until August 28, 08:00pm

    NOW until 8:00pm Fri

    Extreme Heat Warning

  • Tonight

    Low: 72 °F

    Mostly Clear
    then Patchy
    Fog

  • Thursday

    Thursday: Patchy fog before 11am. Otherwise, mostly cloudy, with a high near 101. Heat index values as high as 106. Calm wind becoming southwest around 5 mph in the afternoon.

    High: 101 °F

    Patchy Fog
    then Mostly
    Cloudy

  • Thursday Night

    Thursday Night: Patchy fog after 11pm. Otherwise, mostly cloudy, with a low around 72. Southwest wind around 5 mph becoming calm in the evening.

    Low: 72 °F

    Patchy Fog

  • Friday

    Friday: Patchy fog before 11am. Otherwise, mostly sunny, with a high near 99. Light south wind becoming southwest 5 to 10 mph in the afternoon.

    High: 99 °F

    Patchy Fog
    then Mostly
    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 72. Southwest wind around 5 mph becoming calm after midnight.

    Low: 72 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 96.

    High: 96 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 69.

    Low: 69 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 89.

    High: 89 °F

    Sunny

Detailed Forecast

Tonight
Patchy fog after 2am. Otherwise, increasing clouds, with a low around 72. South wind around 5 mph becoming calm in the evening.
Thursday
Patchy fog before 11am. Otherwise, mostly cloudy, with a high near 101. Heat index values as high as 106. Calm wind becoming southwest around 5 mph in the afternoon.
Thursday Night
Patchy fog after 11pm. Otherwise, mostly cloudy, with a low around 72. Southwest wind around 5 mph becoming calm in the evening.
Friday
Patchy fog before 11am. Otherwise, mostly sunny, with a high near 99. Light south wind becoming southwest 5 to 10 mph in the afternoon.
Friday Night
Mostly clear, with a low around 72. Southwest wind around 5 mph becoming calm after midnight.
Saturday
Sunny, with a high near 96.
Saturday Night
Clear, with a low around 69.
Sunday
Sunny, with a high near 89.
Sunday Night
Mostly clear, with a low around 66.
Monday
Sunny, with a high near 86.
Monday Night
A slight chance of showers. Mostly clear, with a low around 65.
Tuesday
A slight chance of showers. Mostly sunny, with a high near 87.
Tuesday Night
A slight chance of showers. Partly cloudy, with a low around 67.
Wednesday
A slight chance of showers. Partly sunny, with a high near 89.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Fullerton CA
 33.89°N 117.94°W (Elev. 197 ft)
Last Update:
11:36 am PDT Aug 26, 2026
Forecast Valid:
7pm PDT Aug 26, 2026-6pm PDT Sep 2, 2026
 
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Additional Resources

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