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.

Partly Cloudy

64°F

18°C

Humidity 63%
Wind Speed SE 13 MPH
Barometer 29.64 in (1003.73 mb)
Dewpoint 52°F (11°C)
Visibility 10.00 mi
Last update 24 Dec 01:47 PM PST
Extended Forecast for

Mount Hamilton CA

Flood Watch December 24, 02:03pm 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, 02:03pm until December 26, 10:00pm

    NOW until 10:00pm Fri

    Flood Watch

  • This Afternoon

    High: 51 °F

    Showers
    Likely

  • Tonight

    Tonight: Showers and possibly a thunderstorm before 7pm, then showers between 7pm and 1am, then showers and possibly a thunderstorm after 1am. Low around 45. Windy, with a south southeast wind 25 to 34 mph, with gusts as high as 55 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

    Low: 45 °F

    Showers and
    Windy

  • Christmas Day

    Christmas Day: Showers and possibly a thunderstorm. Steady temperature around 47. Windy, with a south southwest wind 25 to 30 mph decreasing to 18 to 23 mph in the afternoon. Winds could gust as high as 45 mph. Chance of precipitation is 80%. New precipitation amounts between three quarters and one inch possible.

    High: 47 °F

    Showers and
    Windy

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm. Low around 45. Breezy, with a south southwest wind 22 to 29 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: 45 °F

    Showers and
    Breezy

  • Friday

    Friday: Showers. High near 51. South wind 9 to 13 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: 51 °F

    Showers

  • Friday Night

    Friday Night: Showers likely, mainly before 10pm. Mostly cloudy, with a low around 43. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 43 °F

    Showers
    Likely then
    Chance
    Showers

  • Saturday

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

    High: 49 °F

    Slight Chance
    Showers

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 39.

    Low: 39 °F

    Mostly Clear

Detailed Forecast

This Afternoon
Showers likely, with thunderstorms also possible after 4pm. Mostly cloudy, with a steady temperature around 51. Southeast wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tonight
Showers and possibly a thunderstorm before 7pm, then showers between 7pm and 1am, then showers and possibly a thunderstorm after 1am. Low around 45. Windy, with a south southeast wind 25 to 34 mph, with gusts 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 47. Windy, with a south southwest wind 25 to 30 mph decreasing to 18 to 23 mph in the afternoon. Winds could gust as high as 45 mph. Chance of precipitation is 80%. New precipitation amounts between three quarters and one inch possible.
Thursday Night
Showers and possibly a thunderstorm. Low around 45. Breezy, with a south southwest wind 22 to 29 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 51. South wind 9 to 13 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 43. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Saturday
A 20 percent chance of showers. Mostly sunny, with a high near 49.
Saturday Night
Mostly clear, with a low around 39.
Sunday
Sunny, with a high near 50.
Sunday Night
Clear, with a low around 40.
Monday
Sunny, with a high near 54.
Monday Night
Mostly clear, with a low around 44.
Tuesday
Sunny, with a high near 58.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Mount Hamilton CA
 37.35°N 121.62°W (Elev. 3406 ft)
Last Update:
12:27 pm PST Dec 24, 2025
Forecast Valid:
2pm PST Dec 24, 2025-6pm PST Dec 30, 2025
 
Forecast Discussion
 
Get as KML Get as XML

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