Critical Fire Weather in the Southern High Plains; Heavy Snow in the Great Lakes and Northeast U.S.

Gusty winds and low relative humidity will bring critical fire weather to the southern High Plains Friday. A winter storm will track across the Great Lakes and Northeast U.S. Friday into Saturday with areas of wintry mix and heavy snow from northern New York through southern Maine. Read More >

Current conditions at

SJSU - Mount Diablo Summit Museum Rooftop (SJS02)

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

NA

29°F

-2°C

Humidity 99%
Wind Speed N 0 MPH
Barometer NA
Dewpoint 28°F (-2°C)
Visibility NA
Last update 19 Feb 11:20 PM PST
Extended Forecast for

3 Miles S Clayton CA

Extreme Cold Warning February 20, 01:00am until February 20, 09:00am
Click here for hazard details and duration
Extreme Cold Warning
  • Tonight

    Tonight: Widespread frost after 2am.  Otherwise, mostly clear, with a low around 32. West southwest wind 8 to 11 mph, with gusts as high as 22 mph.

    Low: 32 °F

    Frost

  • Friday

    Friday: Widespread frost before 8am.  Otherwise, mostly sunny, with a high near 46. South southeast wind around 6 mph becoming north northwest in the afternoon.

    High: 46 °F

    Frost then
    Partly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 36. Southeast wind 6 to 9 mph.

    Low: 36 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 53. South southeast wind 10 to 14 mph, with gusts as high as 25 mph.

    High: 53 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: A 20 percent chance of rain after 10pm.  Partly cloudy, with a low around 46. South southeast wind around 16 mph, with gusts as high as 31 mph.  New precipitation amounts of less than a tenth of an inch possible.

    Low: 46 °F

    Slight Chance
    Rain

  • Sunday

    Sunday: A 40 percent chance of rain.  Partly sunny, with a high near 60. New precipitation amounts of less than a tenth of an inch possible.

    High: 60 °F

    Chance Rain

  • Sunday Night

    Sunday Night: A 30 percent chance of rain.  Mostly cloudy, with a low around 50.

    Low: 50 °F

    Chance Rain

  • Monday

    Monday: A chance of rain.  Partly sunny, with a high near 61.

    High: 61 °F

    Chance Rain

  • Monday Night

    Monday Night: Rain.  Mostly cloudy, with a low around 55.

    Low: 55 °F

    Rain

Detailed Forecast

Tonight
Widespread frost after 2am. Otherwise, mostly clear, with a low around 32. West southwest wind 8 to 11 mph, with gusts as high as 22 mph.
Friday
Widespread frost before 8am. Otherwise, mostly sunny, with a high near 46. South southeast wind around 6 mph becoming north northwest in the afternoon.
Friday Night
Partly cloudy, with a low around 36. Southeast wind 6 to 9 mph.
Saturday
Mostly sunny, with a high near 53. South southeast wind 10 to 14 mph, with gusts as high as 25 mph.
Saturday Night
A 20 percent chance of rain after 10pm. Partly cloudy, with a low around 46. South southeast wind around 16 mph, with gusts as high as 31 mph. New precipitation amounts of less than a tenth of an inch possible.
Sunday
A 40 percent chance of rain. Partly sunny, with a high near 60. New precipitation amounts of less than a tenth of an inch possible.
Sunday Night
A 30 percent chance of rain. Mostly cloudy, with a low around 50.
Monday
A chance of rain. Partly sunny, with a high near 61.
Monday Night
Rain. Mostly cloudy, with a low around 55.
Tuesday
Rain. Mostly cloudy, with a high near 56.
Tuesday Night
Rain. Mostly cloudy, with a low around 52.
Wednesday
Rain likely. Mostly cloudy, with a high near 58.
Wednesday Night
A chance of rain. Mostly cloudy, with a low around 50.
Thursday
A chance of rain. Mostly sunny, with a high near 60.
Basemap Options
Click map to change the forecast location
Loading map...

ABOUT THIS FORECAST

 
Point Forecast:
3 Miles S Clayton CA
 37.9°N 121.92°W (Elev. 1900 ft)
8:22 pm PST Feb 19, 2026
11pm PST Feb 19, 2026-6pm PST Feb 26, 2026
 
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