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Tracking Winter Weather and Frigid Temperatures Through This Weekend

A clipper storm will move across the Great Lakes through this weekend with periods of light snow, gusty winds, and lake effect snow bands which could make for hazardous travel at times. A frigid airmass will spread eastward behind this storm into the Midwest and Eastern U.S. through the weekend. Read More >

Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

50°F

10°C

Humidity 18%
Wind Speed NE 20 G 25 mph
Barometer 30.31 in (1026.2 mb)
Dewpoint 8°F (-13°C)
Visibility 10.00 mi
Wind Chill44°F (7°C)
Last update 17 Jan 9:56 am CST
Extended Forecast for

4 Miles WNW San Marcos TX

Red Flag Warning until January 17, 08:00pm
Click here for hazard details and duration
Red Flag Warning
  •  
    Red Flag Warning until January 17, 08:00pm

    NOW until 8:00pm Sat

    Red Flag Warning

  • Today

    High: 56 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 28. North northeast wind 5 to 15 mph becoming west northwest after midnight. Winds could gust as high as 25 mph.

    Low: 28 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 61. West northwest wind 5 to 10 mph becoming southwest in the afternoon.

    High: 61 °F

    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 34. Southwest wind around 5 mph.

    Low: 34 °F

    Clear

  • M.L.King Day

    M.L.King Day: Sunny, with a high near 64. West southwest wind 5 to 10 mph becoming east southeast in the afternoon.

    High: 64 °F

    Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 39. East wind around 5 mph becoming north northeast after midnight.

    Low: 39 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 59. Northeast wind around 5 mph becoming southeast in the afternoon.

    High: 59 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Cloudy, with a low around 49. South southeast wind around 5 mph.

    Low: 49 °F

    Cloudy then
    Slight Chance
    Showers

Detailed Forecast

Today
Sunny, with a high near 56. North northeast wind around 15 mph, with gusts as high as 30 mph.
Tonight
Mostly clear, with a low around 28. North northeast wind 5 to 15 mph becoming west northwest after midnight. Winds could gust as high as 25 mph.
Sunday
Sunny, with a high near 61. West northwest wind 5 to 10 mph becoming southwest in the afternoon.
Sunday Night
Clear, with a low around 34. Southwest wind around 5 mph.
M.L.King Day
Sunny, with a high near 64. West southwest wind 5 to 10 mph becoming east southeast in the afternoon.
Monday Night
Mostly cloudy, with a low around 39. East wind around 5 mph becoming north northeast after midnight.
Tuesday
Mostly cloudy, with a high near 59. Northeast wind around 5 mph becoming southeast in the afternoon.
Tuesday Night
A 20 percent chance of showers after midnight. Cloudy, with a low around 49. South southeast wind around 5 mph.
Wednesday
A 30 percent chance of showers. Mostly cloudy, with a high near 65. South wind around 5 mph.
Wednesday Night
Mostly cloudy, with a low around 49.
Thursday
Mostly sunny, with a high near 67.
Thursday Night
Partly cloudy, with a low around 41.
Friday
Mostly cloudy, with a high near 61.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles WNW San Marcos TX
 29.9°N 97.99°W (Elev. 850 ft)
Last Update:
9:16 am CST Jan 17, 2026
Forecast Valid:
10am CST Jan 17, 2026-6pm CST Jan 23, 2026
 
Forecast Discussion
 
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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

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation