Prolonged Extreme Cold; Eastern U.S. Winter Storm

Another Arctic blast will surge south across the northern Plains tonight, crossing the Midwest and reaching the Gulf Coast Friday night. Dangerously cold temperatures will persist across the eastern U.S. into early February. There is increasing confidence for significant heavy snow across much of the Southern Appalachians, Carolinas, and southern Mid-Atlantic Friday into Sunday. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

71°F

22°C

Humidity 39%
Wind Speed SW 16 mph
Barometer 30.05 in (1017.4 mb)
Dewpoint 45°F (7°C)
Visibility 10.00 mi
Last update 29 Jan 2:56 pm CST
Extended Forecast for

4 Miles WNW San Marcos TX

Cold Weather Advisory January 31, 03:00am until January 31, 10:00am
Click here for hazard details and duration
Cold Weather Advisory
  • This Afternoon

    This Afternoon: Sunny, with a high near 70. West southwest wind around 10 mph, with gusts as high as 20 mph.

    High: 70 °F

    Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 36. North wind 5 to 10 mph, with gusts as high as 25 mph.

    Low: 36 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly cloudy, then gradual clearing during the afternoon, with a high near 56. North wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 56 °F

    Becoming
    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 28. North wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 28 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 42. North northeast wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 42 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 21. Northeast wind around 5 mph becoming calm  in the evening.

    Low: 21 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 55. Calm wind becoming south around 5 mph in the morning.

    High: 55 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 35. West southwest wind around 5 mph.

    Low: 35 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 63. West wind around 5 mph becoming south southeast in the afternoon.

    High: 63 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 70. West southwest wind around 10 mph, with gusts as high as 20 mph.
Tonight
Mostly cloudy, with a low around 36. North wind 5 to 10 mph, with gusts as high as 25 mph.
Friday
Mostly cloudy, then gradual clearing during the afternoon, with a high near 56. North wind 10 to 15 mph, with gusts as high as 20 mph.
Friday Night
Mostly clear, with a low around 28. North wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday
Sunny, with a high near 42. North northeast wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Clear, with a low around 21. Northeast wind around 5 mph becoming calm in the evening.
Sunday
Sunny, with a high near 55. Calm wind becoming south around 5 mph in the morning.
Sunday Night
Mostly clear, with a low around 35. West southwest wind around 5 mph.
Monday
Mostly sunny, with a high near 63. West wind around 5 mph becoming south southeast in the afternoon.
Monday Night
Mostly cloudy, with a low around 50.
Tuesday
Mostly cloudy, with a high near 71.
Tuesday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 50.
Wednesday
A 30 percent chance of showers. Mostly cloudy, with a high near 63.
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles WNW San Marcos TX
 29.9°N 97.99°W (Elev. 850 ft)
2:46 pm CST Jan 29, 2026
3pm CST Jan 29, 2026-6pm CST Feb 4, 2026
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database