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 Francisco, San Francisco International Airport (KSFO)

Lat: 37.61961°NLon: 122.36558°WElev: 10.0ft.

Mostly Cloudy

57°F

14°C

Humidity 71%
Wind Speed SW 24 MPH
Barometer 29.67 in (1004.74 mb)
Dewpoint 48°F (9°C)
Visibility 8.00 mi
Last update 25 Dec 05:35 AM PST
Extended Forecast for

Belmont CA

Flood Watch December 25, 05:50am until December 26, 10:00pm
Wind Advisory December 25, 05:50am until December 25, 10:00am
Flood Advisory December 25, 05:50am until December 25, 06:30am
Click here for hazard details and duration
Flood Watch
Wind Advisory
Flood Advisory
  •  
    Flood Watch December 25, 05:50am until December 26, 10:00pm
    Wind Advisory December 25, 05:50am until December 25, 10:00am
    Flood Advisory December 25, 05:50am until December 25, 06:30am

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Overnight

    Low: 51 °F

    Severe
    Thunderstorms

  • Christmas Day

    Christmas Day: Showers and possibly a thunderstorm before 7am, then rain between 7am and 10am, then showers and possibly a thunderstorm after 10am. Some of the storms could be severe. High near 57. Breezy, with a south wind 20 to 25 mph, with gusts as high as 43 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.

    High: 57 °F

    Severe
    Thunderstorms
    and Breezy

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm before 10pm, then rain likely after 10pm. Some of the storms could be severe. Steady temperature around 51. Breezy, with a south southwest wind 21 to 26 mph decreasing to 14 to 19 mph after midnight. Winds could gust as high as 43 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 51 °F

    Severe
    Thunderstorms
    and Breezy
    then Rain
    Likely

  • Friday

    Friday: Rain. High near 56. South wind around 14 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 56 °F

    Rain

  • Friday Night

    Friday Night: Rain likely, mainly before 10pm. Mostly cloudy, with a low around 45. West wind 7 to 9 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 45 °F

    Rain Likely
    then Chance
    Rain

  • Saturday

    Saturday: A 20 percent chance of rain. Mostly sunny, with a high near 54.

    High: 54 °F

    Slight Chance
    Rain

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 40.

    Low: 40 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 54.

    High: 54 °F

    Mostly Sunny

Detailed Forecast

Overnight
Showers and possibly a thunderstorm. Some of the storms could be severe. Low around 51. South southwest wind around 21 mph, with gusts as high as 40 mph. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Christmas Day
Showers and possibly a thunderstorm before 7am, then rain between 7am and 10am, then showers and possibly a thunderstorm after 10am. Some of the storms could be severe. High near 57. Breezy, with a south wind 20 to 25 mph, with gusts as high as 43 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Thursday Night
Showers and possibly a thunderstorm before 10pm, then rain likely after 10pm. Some of the storms could be severe. Steady temperature around 51. Breezy, with a south southwest wind 21 to 26 mph decreasing to 14 to 19 mph after midnight. Winds could gust as high as 43 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.
Friday
Rain. High near 56. South wind around 14 mph, with gusts as high as 23 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday Night
Rain likely, mainly before 10pm. Mostly cloudy, with a low around 45. West wind 7 to 9 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Saturday
A 20 percent chance of rain. Mostly sunny, with a high near 54.
Saturday Night
Mostly clear, with a low around 40.
Sunday
Mostly sunny, with a high near 54.
Sunday Night
Mostly clear, with a low around 38.
Monday
Sunny, with a high near 57.
Monday Night
Mostly clear, with a low around 39.
Tuesday
Sunny, with a high near 58.
Tuesday Night
Partly cloudy, with a low around 41.
Wednesday
Partly sunny, with a high near 59.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Belmont CA
 37.52°N 122.31°W (Elev. 397 ft)
Last Update:
12:27 am PST Dec 25, 2025
Forecast Valid:
5am PST Dec 25, 2025-6pm PST Dec 31, 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