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

Snow Squalls May Impact New Year's Eve Travel from the Great Lakes to the Mid-Atlantic; Heavy Rain & Isolated Severe Thunderstorms in Southern California

Snow squalls are likely to cross the Lower Great Lakes this evening and the Ohio Valley through the interior Northeast/northern Mid-Atlantic overnight, before potentially reaching the I-95 corridor from D.C. to New York City early New Year’s Day morning. Heavy rain and isolated severe thunderstorms will impact coastal southern California including Los Angeles tonight into early on New Year's Day. Read More >

Current conditions at

SJSU - Mount Diablo Summit Museum Rooftop (SJS02)

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

NA

46°F

8°C

Humidity 99%
Wind Speed SE 12 MPH
Barometer NA
Dewpoint 45°F (7°C)
Visibility NA
Wind Chill40°F (4°C)
Last update 31 Dec 11:35 PM PST
Extended Forecast for

4 Miles SSE Clayton CA

  • Tonight

    Tonight: Rain. Low around 45. Southeast wind 11 to 13 mph, with gusts as high as 25 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 45 °F

    Rain

  • New Year's Day

    New Year's Day: Rain likely, mainly before 4pm. Mostly cloudy, with a high near 51. South wind 13 to 17 mph, with gusts as high as 23 mph. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.

    High: 51 °F

    Rain Likely

  • Thursday Night

    Thursday Night: A 40 percent chance of rain, mainly before 10pm. Mostly cloudy, with a steady temperature around 49. South wind 10 to 14 mph, with gusts as high as 23 mph. New precipitation amounts of less than a tenth of an inch possible.

    Low: 49 °F

    Chance Rain

  • Friday

    Friday: Rain likely, mainly after 4pm. Mostly cloudy, with a high near 55. South wind 11 to 15 mph, with gusts as high as 23 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.

    High: 55 °F

    Rain Likely

  • Friday Night

    Friday Night: Rain. Low around 52. Breezy, with a south wind 20 to 24 mph, with gusts as high as 41 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 52 °F

    Rain and
    Breezy

  • Saturday

    Saturday: Rain before 10am, then showers and possibly a thunderstorm after 10am. High near 56. Breezy. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    High: 56 °F

    Showers and
    Breezy

  • Saturday Night

    Saturday Night: Showers and possibly a thunderstorm. Low around 49. Chance of precipitation is 90%.

    Low: 49 °F

    Showers

  • Sunday

    Sunday: Rain. Cloudy, with a high near 53.

    High: 53 °F

    Rain

  • Sunday Night

    Sunday Night: Rain. Mostly cloudy, with a low around 48.

    Low: 48 °F

    Rain

Detailed Forecast

Tonight
Rain. Low around 45. Southeast wind 11 to 13 mph, with gusts as high as 25 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
New Year's Day
Rain likely, mainly before 4pm. Mostly cloudy, with a high near 51. South wind 13 to 17 mph, with gusts as high as 23 mph. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.
Thursday Night
A 40 percent chance of rain, mainly before 10pm. Mostly cloudy, with a steady temperature around 49. South wind 10 to 14 mph, with gusts as high as 23 mph. New precipitation amounts of less than a tenth of an inch possible.
Friday
Rain likely, mainly after 4pm. Mostly cloudy, with a high near 55. South wind 11 to 15 mph, with gusts as high as 23 mph. Chance of precipitation is 60%. New precipitation amounts of less than a tenth of an inch possible.
Friday Night
Rain. Low around 52. Breezy, with a south wind 20 to 24 mph, with gusts as high as 41 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Saturday
Rain before 10am, then showers and possibly a thunderstorm after 10am. High near 56. Breezy. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Saturday Night
Showers and possibly a thunderstorm. Low around 49. Chance of precipitation is 90%.
Sunday
Rain. Cloudy, with a high near 53.
Sunday Night
Rain. Mostly cloudy, with a low around 48.
Monday
Rain likely. Mostly cloudy, with a high near 51.
Monday Night
Rain likely. Mostly cloudy, with a low around 46.
Tuesday
A chance of rain. Partly sunny, with a high near 49.
Tuesday Night
A slight chance of rain. Partly cloudy, with a low around 43.
Wednesday
A chance of rain. Partly sunny, with a high near 48.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles SSE Clayton CA
 37.87°N 121.92°W (Elev. 2818 ft)
Last Update:
2:14 pm PST Dec 31, 2025
Forecast Valid:
11pm PST Dec 31, 2025-6pm PST Jan 7, 2026
 
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