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

Heavy Rainfall to Bring Flooding Threat to California; Heavy Snow in the Sierra

A strong atmospheric river will bring heavy rainfall to California through the holiday week. The heaviest rainfall is expected on Wednesday in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall is expected in the Sierra Nevada from the atmospheric river, raising concerns for major snow‐load impacts. Travel may be difficult to impossible over the passes. Read More >

Hazardous Weather Conditions

Current conditions at

SJSU - Mount Diablo Summit Museum Rooftop (SJS02)

Lat: 37.881699°NLon: 121.914173°WElev: 3904.0ft.

NA

48°F

9°C

Humidity 100%
Wind Speed S 27 MPH
Barometer NA
Dewpoint 48°F (9°C)
Visibility NA
Wind Chill40°F (4°C)
Last update 24 Dec 01:55 AM PST
Extended Forecast for

4 Miles ENE Danville CA

Flood Watch December 24, 02:09am until December 26, 10:00pm
Wind Advisory until December 24, 04:00am
Click here for hazard details and duration
Flood Watch
Wind Advisory
  •  
    Flood Watch December 24, 02:09am until December 26, 10:00pm
    Wind Advisory until December 24, 04:00am

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Overnight

    Low: 49 °F

    Showers and
    Breezy

  • Wednesday

    Wednesday: A chance of showers before 4pm, then a chance of showers and thunderstorms between 4pm and 5pm, then showers and possibly a thunderstorm after 5pm. Some of the storms could be severe. High near 58. South southeast wind 7 to 14 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 58 °F

    Chance
    Showers then
    Severe
    Thunderstorms

  • Wednesday Night

    Wednesday Night: Showers and thunderstorms likely before 2am, then showers between 2am and 4am, then showers and possibly a thunderstorm after 4am. Some of the storms could be severe. Low around 48. Breezy, with a southeast wind 17 to 22 mph increasing to 23 to 28 mph after midnight. Winds could gust as high as 48 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 48 °F

    Severe
    Thunderstorms
    and Breezy

  • Christmas Day

    Christmas Day: Showers and possibly a thunderstorm. Some of the storms could be severe. High near 55. Breezy, with a south wind 18 to 22 mph, with gusts as high as 44 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.

    High: 55 °F

    Severe
    Thunderstorms
    and Breezy
    then Showers

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm. Some of the storms could be severe. Low around 46. South wind 11 to 13 mph, with gusts as high as 29 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 46 °F

    Severe
    Thunderstorms

  • Friday

    Friday: Showers, with thunderstorms also possible after 4pm. High near 55. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 55 °F

    Showers

  • Friday Night

    Friday Night: Showers likely and possibly a thunderstorm before 10pm, then a chance of showers and thunderstorms, mainly between 10pm and 4am. Mostly cloudy, with a low around 41. Chance of precipitation is 60%.

    Low: 41 °F

    Showers
    Likely

  • Saturday

    Saturday: A slight chance of showers before 10am. Patchy fog before 11am. Otherwise, partly sunny, with a high near 53.

    High: 53 °F

    Slight Chance
    Showers and
    Patchy Fog
    then Partly
    Sunny

Detailed Forecast

Overnight
Showers. Low around 49. Breezy, with a south southeast wind around 29 mph, with gusts as high as 55 mph. Chance of precipitation is 100%. New precipitation amounts between a tenth and quarter of an inch possible.
Wednesday
A chance of showers before 4pm, then a chance of showers and thunderstorms between 4pm and 5pm, then showers and possibly a thunderstorm after 5pm. Some of the storms could be severe. High near 58. South southeast wind 7 to 14 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
Showers and thunderstorms likely before 2am, then showers between 2am and 4am, then showers and possibly a thunderstorm after 4am. Some of the storms could be severe. Low around 48. Breezy, with a southeast wind 17 to 22 mph increasing to 23 to 28 mph after midnight. Winds could gust as high as 48 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Christmas Day
Showers and possibly a thunderstorm. Some of the storms could be severe. High near 55. Breezy, with a south wind 18 to 22 mph, with gusts as high as 44 mph. Chance of precipitation is 100%. New precipitation amounts between a quarter and half of an inch possible.
Thursday Night
Showers and possibly a thunderstorm. Some of the storms could be severe. Low around 46. South wind 11 to 13 mph, with gusts as high as 29 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Friday
Showers, with thunderstorms also possible after 4pm. High near 55. Chance of precipitation is 90%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday Night
Showers likely and possibly a thunderstorm before 10pm, then a chance of showers and thunderstorms, mainly between 10pm and 4am. Mostly cloudy, with a low around 41. Chance of precipitation is 60%.
Saturday
A slight chance of showers before 10am. Patchy fog before 11am. Otherwise, partly sunny, with a high near 53.
Saturday Night
Areas of frost after 3am. Otherwise, mostly clear, with a low around 35.
Sunday
Areas of frost before 8am. Otherwise, sunny, with a high near 51.
Sunday Night
Patchy frost. Otherwise, mostly clear, with a low around 34.
Monday
Mostly sunny, with a high near 53.
Monday Night
Patchy frost. Otherwise, partly cloudy, with a low around 36.
Tuesday
Areas of frost. Otherwise, mostly sunny, with a high near 55.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles ENE Danville CA
 37.85°N 121.94°W (Elev. 1362 ft)
Last Update:
1:25 am PST Dec 24, 2025
Forecast Valid:
2am PST Dec 24, 2025-6pm PST Dec 30, 2025
 
Forecast Discussion
 
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