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

WHITTIER HILLS (WTHC1)

Lat: 33.984°NLon: 118.00943°WElev: 950.0ft.

NA

59°F

15°C

Humidity 100%
Wind Speed SW 3 MPH
Barometer NA
Dewpoint 59°F (15°C)
Visibility NA
Last update 25 Jun 01:57 AM PDT
Extended Forecast for

Diamond Bar CA

  • Overnight

    Overnight: Mostly cloudy, with a low around 64. Calm wind.

    Low: 64 °F

    Mostly Cloudy

  • Thursday

    Thursday: Patchy fog before 11am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 86. Light southwest wind increasing to 5 to 10 mph in the afternoon. Winds could gust as high as 15 mph.

    High: 86 °F

    Patchy Fog
    then Sunny

  • Thursday Night

    Thursday Night: Increasing clouds, with a low around 57. Southwest wind 5 to 10 mph becoming light south southwest after midnight. Winds could gust as high as 15 mph.

    Low: 57 °F

    Increasing
    Clouds

  • Friday

    Friday: Patchy fog before 11am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 80. Light south wind becoming southwest 5 to 10 mph in the morning. Winds could gust as high as 15 mph.

    High: 80 °F

    Patchy Fog
    then Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 57. Southwest wind 5 to 10 mph, with gusts as high as 15 mph.

    Low: 57 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 72.

    High: 72 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Patchy fog after 11pm. Otherwise, mostly cloudy, with a low around 55.

    Low: 55 °F

    Patchy Fog

  • Sunday

    Sunday: Patchy fog before 11am. Otherwise, mostly sunny, with a high near 72.

    High: 72 °F

    Patchy Fog
    then Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 55.

    Low: 55 °F

    Mostly Clear

Detailed Forecast

Overnight
Mostly cloudy, with a low around 64. Calm wind.
Thursday
Patchy fog before 11am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 86. Light southwest wind increasing to 5 to 10 mph in the afternoon. Winds could gust as high as 15 mph.
Thursday Night
Increasing clouds, with a low around 57. Southwest wind 5 to 10 mph becoming light south southwest after midnight. Winds could gust as high as 15 mph.
Friday
Patchy fog before 11am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 80. Light south wind becoming southwest 5 to 10 mph in the morning. Winds could gust as high as 15 mph.
Friday Night
Mostly clear, with a low around 57. Southwest wind 5 to 10 mph, with gusts as high as 15 mph.
Saturday
Mostly sunny, with a high near 72.
Saturday Night
Patchy fog after 11pm. Otherwise, mostly cloudy, with a low around 55.
Sunday
Patchy fog before 11am. Otherwise, mostly sunny, with a high near 72.
Sunday Night
Mostly clear, with a low around 55.
Monday
Mostly sunny, with a high near 74.
Monday Night
Mostly clear, with a low around 55.
Tuesday
Mostly sunny, with a high near 74.
Tuesday Night
Mostly clear, with a low around 55.
Wednesday
Sunny, with a high near 76.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Diamond Bar CA
 34°N 117.82°W (Elev. 1014 ft)
Last Update:
1:52 am PDT Jun 25, 2026
Forecast Valid:
2am PDT Jun 25, 2026-6pm PDT Jul 1, 2026
 
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