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

Atmospheric River Bringing Heavy Rain to Southern California and Heavy Snow to the Sierra Nevadas

A strong atmospheric river will continue heavy rain over southern California through Friday. The heaviest rainfall is ongoing today in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall has begun over the Sierra Nevada Mountains and will continue through Friday. Travel will become increasingly difficult over the passes due to snow and strong winds. Read More >

Hazardous Weather Conditions

Current conditions at

San Jose / Reid / Hillv (KRHV)

Lat: 37.33333°NLon: 121.81667°WElev: 135.0ft.

Mostly Cloudy

59°F

15°C

Humidity 82%
Wind Speed SE 20 MPH
Barometer 29.64 in (1003.73 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 24 Dec 06:47 PM PST
Extended Forecast for

Mount Hamilton CA

Flood Watch December 24, 07:13pm until December 26, 10:00pm
Wind Advisory December 24, 08:00pm until December 25, 10:00am
Click here for hazard details and duration
Flood Watch
Wind Advisory
  •  
    Flood Watch December 24, 07:13pm until December 26, 10:00pm

    NOW until 10:00pm Fri

    Flood Watch

  • Tonight

    Low: 49 °F

    Showers and
    Windy

  • Christmas Day

    Christmas Day: Showers and possibly a thunderstorm. Steady temperature around 46. Breezy, with a southwest wind 20 to 28 mph, with gusts as high as 40 mph. Chance of precipitation is 80%. New precipitation amounts between three quarters and one inch possible.

    High: 46 °F

    Showers and
    Breezy

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm. Steady temperature around 47. Windy, with a south southwest wind 22 to 30 mph, with gusts as high as 50 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.

    Low: 47 °F

    Showers and
    Windy

  • Friday

    Friday: Showers. High near 48. South wind 10 to 14 mph, with gusts as high as 22 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 48 °F

    Showers

  • Friday Night

    Friday Night: Showers likely, mainly before 10pm. Mostly cloudy, with a low around 40. South wind around 6 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 40 °F

    Showers
    Likely then
    Chance
    Showers

  • Saturday

    Saturday: A 20 percent chance of showers before 10am. Mostly sunny, with a high near 49.

    High: 49 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 35.

    Low: 35 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 50.

    High: 50 °F

    Sunny

Detailed Forecast

Tonight
Showers, with thunderstorms also possible after 1am. Steady temperature around 49. Windy, with a south southeast wind 23 to 28 mph increasing to 31 to 36 mph in the evening. Winds could gust as high as 55 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.
Christmas Day
Showers and possibly a thunderstorm. Steady temperature around 46. Breezy, with a southwest wind 20 to 28 mph, with gusts as high as 40 mph. Chance of precipitation is 80%. New precipitation amounts between three quarters and one inch possible.
Thursday Night
Showers and possibly a thunderstorm. Steady temperature around 47. Windy, with a south southwest wind 22 to 30 mph, with gusts as high as 50 mph. Chance of precipitation is 100%. New precipitation amounts between a half and three quarters of an inch possible.
Friday
Showers. High near 48. South wind 10 to 14 mph, with gusts as high as 22 mph. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday Night
Showers likely, mainly before 10pm. Mostly cloudy, with a low around 40. South wind around 6 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Saturday
A 20 percent chance of showers before 10am. Mostly sunny, with a high near 49.
Saturday Night
Mostly clear, with a low around 35.
Sunday
Sunny, with a high near 50.
Sunday Night
Clear, with a low around 36.
Monday
Sunny, with a high near 54.
Monday Night
Mostly clear, with a low around 41.
Tuesday
Sunny, with a high near 58.
Tuesday Night
Mostly clear, with a low around 44.
Wednesday
A slight chance of showers. Mostly sunny, with a high near 58.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Mount Hamilton CA
 37.35°N 121.64°W (Elev. 2398 ft)
Last Update:
4:56 pm PST Dec 24, 2025
Forecast Valid:
7pm PST Dec 24, 2025-6pm PST Dec 31, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation