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

Santa Rosa, Santa Rosa Sonoma County Airport (KSTS)

Lat: 38.5°NLon: 122.81667°WElev: 125.0ft.

Partly Cloudy

61°F

16°C

Humidity 59%
Wind Speed SSE 4 MPH
Barometer 29.62 in (1003.05 mb)
Dewpoint 46°F (8°C)
Visibility 10.00 mi
Last update 24 Dec 01:20 PM PST
Extended Forecast for

Saint Helena CA

Flood Watch December 24, 01:31pm 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, 01:31pm until December 26, 10:00pm

    NOW until 10:00pm Fri

    Flood Watch

  • This Afternoon

    High: 56 °F

    Severe
    Thunderstorms

  • Tonight

    Tonight: Showers and possibly a thunderstorm. Some of the storms could be severe. Low around 47. Breezy, with a south southeast wind 13 to 23 mph, with gusts as high as 49 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

    Low: 47 °F

    Breezy.
    Severe
    Thunderstorms
    then Showers

  • Christmas Day

    Christmas Day: Showers, with thunderstorms also possible after 10am. High near 52. South wind 9 to 17 mph, with gusts as high as 32 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.

    High: 52 °F

    Showers

  • Thursday Night

    Thursday Night: Showers. Low around 45. Southeast wind 8 to 15 mph becoming southwest in the evening. Winds could gust as high as 43 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.

    Low: 45 °F

    Showers

  • Friday

    Friday: Showers. High near 52. South wind 3 to 5 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 52 °F

    Showers

  • Friday Night

    Friday Night: A chance of showers and thunderstorms. Patchy fog. Otherwise, mostly cloudy, with a low around 39. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 39 °F

    Chance
    Showers and
    Patchy Fog

  • Saturday

    Saturday: A 20 percent chance of showers before 10am. Areas of fog before 10am. Otherwise, mostly sunny, with a high near 53.

    High: 53 °F

    Slight Chance
    Showers and
    Areas Fog
    then Sunny

  • Saturday Night

    Saturday Night: Patchy frost after 2am. Otherwise, mostly clear, with a low around 36.

    Low: 36 °F

    Mostly Clear
    then Patchy
    Frost

Detailed Forecast

This Afternoon
A chance of showers, with thunderstorms also possible after 4pm. Some of the storms could be severe. Mostly cloudy, with a high near 56. Southeast wind 8 to 10 mph. Chance of precipitation is 50%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tonight
Showers and possibly a thunderstorm. Some of the storms could be severe. Low around 47. Breezy, with a south southeast wind 13 to 23 mph, with gusts as high as 49 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.
Christmas Day
Showers, with thunderstorms also possible after 10am. High near 52. South wind 9 to 17 mph, with gusts as high as 32 mph. Chance of precipitation is 100%. New rainfall amounts between a half and three quarters of an inch possible.
Thursday Night
Showers. Low around 45. Southeast wind 8 to 15 mph becoming southwest in the evening. Winds could gust as high as 43 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.
Friday
Showers. High near 52. South wind 3 to 5 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible.
Friday Night
A chance of showers and thunderstorms. Patchy fog. Otherwise, mostly cloudy, with a low around 39. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Saturday
A 20 percent chance of showers before 10am. Areas of fog before 10am. Otherwise, mostly sunny, with a high near 53.
Saturday Night
Patchy frost after 2am. Otherwise, mostly clear, with a low around 36.
Sunday
Areas of frost before 8am. Otherwise, mostly sunny, with a high near 54.
Sunday Night
Patchy frost after 2am. Otherwise, mostly clear, with a low around 36.
Monday
Areas of frost. Otherwise, sunny, with a high near 57.
Monday Night
Patchy fog. Patchy frost. Otherwise, mostly clear, with a low around 36.
Tuesday
Patchy fog. Patchy frost. Otherwise, sunny, with a high near 58.
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ABOUT THIS FORECAST

 
Point Forecast:
Saint Helena CA
 38.51°N 122.46°W (Elev. 203 ft)
Last Update:
12:27 pm PST Dec 24, 2025
Forecast Valid:
1pm PST Dec 24, 2025-6pm PST Dec 30, 2025
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation