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

BLACK DIAMOND (PIBC1)

Lat: 37.95°NLon: 121.88444°WElev: 1600.0ft.

NA

59°F

15°C

Humidity 72%
Wind Speed NNE 19 MPH
Barometer NA
Dewpoint 50°F (10°C)
Visibility NA
Last update 24 Dec 12:28 AM PST
Extended Forecast for

Pittsburg CA

Flood Watch December 24, 01:07am 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, 01:07am until December 26, 10:00pm
    Wind Advisory until December 24, 04:00am

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Overnight

    Low: 56 °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. Steady temperature around 57. Light and variable wind becoming south southeast 9 to 14 mph in the morning. Winds could gust 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: 57 °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. Steady temperature around 57. Southeast wind 16 to 20 mph, with gusts as high as 36 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 57 °F

    Severe
    Thunderstorms
    then Showers

  • Christmas Day

    Christmas Day: Showers and thunderstorms before 9am, then showers and possibly a thunderstorm between 9am and 10am, then showers after 10am. High near 56. Breezy, with a south wind 15 to 20 mph increasing to 21 to 26 mph in the morning. 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.

    High: 56 °F

    Showers and
    Breezy

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm. Low around 50. Breezy, with a south wind 20 to 22 mph, with gusts as high as 40 mph. Chance of precipitation is 100%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 50 °F

    Showers and
    Breezy

  • Friday

    Friday: Showers, with thunderstorms also possible after 4pm. High near 52. Breezy. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 52 °F

    Showers and
    Breezy

  • 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 46. Chance of precipitation is 60%.

    Low: 46 °F

    Showers
    Likely

  • Saturday

    Saturday: A slight chance of showers before 10am. Mostly cloudy, with a high near 51.

    High: 51 °F

    Slight Chance
    Showers then
    Partly Sunny

Detailed Forecast

Overnight
Showers. Low around 56. Breezy, with a southeast wind 18 to 23 mph, with gusts as high as 39 mph. Chance of precipitation is 90%. 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. Steady temperature around 57. Light and variable wind becoming south southeast 9 to 14 mph in the morning. Winds could gust 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. Steady temperature around 57. Southeast wind 16 to 20 mph, with gusts as high as 36 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Christmas Day
Showers and thunderstorms before 9am, then showers and possibly a thunderstorm between 9am and 10am, then showers after 10am. High near 56. Breezy, with a south wind 15 to 20 mph increasing to 21 to 26 mph in the morning. 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.
Thursday Night
Showers and possibly a thunderstorm. Low around 50. Breezy, with a south wind 20 to 22 mph, with gusts as high as 40 mph. Chance of precipitation is 100%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday
Showers, with thunderstorms also possible after 4pm. High near 52. Breezy. Chance of precipitation is 80%. 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 46. Chance of precipitation is 60%.
Saturday
A slight chance of showers before 10am. Mostly cloudy, with a high near 51.
Saturday Night
Mostly clear, with a low around 40.
Sunday
Sunny, with a high near 48.
Sunday Night
Partly cloudy, with a low around 38.
Monday
Patchy fog. Otherwise, partly sunny, with a high near 48.
Monday Night
Partly cloudy, with a low around 39.
Tuesday
Patchy fog. Otherwise, partly sunny, with a high near 50.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Pittsburg CA
 38.04°N 121.87°W (Elev. 3 ft)
Last Update:
12:27 am PST Dec 24, 2025
Forecast Valid:
1am PST Dec 24, 2025-6pm PST Dec 30, 2025
 
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