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

Snow Squalls May Impact the Northeast on Thursday; Dangerously Cold Arctic Air Impact the North-Central US

Snow showers and snow squalls are likely to develop across the Northeast on Thursday. Lake effect snow will persist downwind of the Great Lakes. An arctic blast will bring frigid temperatures, gusty winds and dangerous wind chills to the Northern Plains before expanding to the South and East. A major winter storm will begin impacting the Southern Plains and Lower Mississippi Valley Friday. Read More >

Current conditions at

SJSU - Mount Diablo Summit Museum Rooftop (SJS02)

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

NA

54°F

12°C

Humidity 28%
Wind Speed W 5 MPH
Barometer NA
Dewpoint 22°F (-6°C)
Visibility NA
Last update 21 Jan 08:50 PM PST
Extended Forecast for

4 Miles S Clayton CA

  • Tonight

    Tonight: Mostly cloudy, with a steady temperature around 50. South wind around 6 mph becoming northwest after midnight.

    Low: 50 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly cloudy, then gradually becoming sunny, with a high near 56. West wind around 6 mph.

    High: 56 °F

    Decreasing
    Clouds

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 44. Southwest wind around 9 mph.

    Low: 44 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 52. West wind around 6 mph becoming north in the morning.

    High: 52 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 42. North northwest wind 6 to 8 mph, with gusts as high as 24 mph.

    Low: 42 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 54.

    High: 54 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 39.

    Low: 39 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 52.

    High: 52 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 41.

    Low: 41 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a steady temperature around 50. South wind around 6 mph becoming northwest after midnight.
Thursday
Mostly cloudy, then gradually becoming sunny, with a high near 56. West wind around 6 mph.
Thursday Night
Partly cloudy, with a low around 44. Southwest wind around 9 mph.
Friday
Mostly sunny, with a high near 52. West wind around 6 mph becoming north in the morning.
Friday Night
Mostly clear, with a low around 42. North northwest wind 6 to 8 mph, with gusts as high as 24 mph.
Saturday
Sunny, with a high near 54.
Saturday Night
Mostly clear, with a low around 39.
Sunday
Mostly sunny, with a high near 52.
Sunday Night
Mostly cloudy, with a low around 41.
Monday
Mostly sunny, with a high near 54.
Monday Night
Partly cloudy, with a low around 41.
Tuesday
Mostly sunny, with a high near 55.
Tuesday Night
Mostly cloudy, with a low around 44.
Wednesday
A slight chance of rain. Partly sunny, with a high near 54.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles S Clayton CA
 37.87°N 121.92°W (Elev. 2818 ft)
Last Update:
2:22 pm PST Jan 21, 2026
Forecast Valid:
9pm PST Jan 21, 2026-6pm PST Jan 28, 2026
 
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Additional Resources

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Chance of Precipitation