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

Tracking Winter Weather and Frigid Temperatures This Weekend

Another clipper will drop into the Northern Plains and Upper Midwest into Sunday with snow and gusty winds contributing to some areas of blizzard conditions and snow squalls. Impactful snowfall will occur up and down the East Coast Sunday extending from the western Florida Panhandle to Maine. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

37°F

3°C

Humidity 41%
Wind Speed N 12 mph
Barometer 30.49 in (1032.5 mb)
Dewpoint 15°F (-9°C)
Visibility 10.00 mi
Wind Chill29°F (-2°C)
Last update 17 Jan 10:56 pm CST
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Clear, with a low around 29. Northwest wind around 5 mph.

    Low: 29 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 61. Northwest wind around 5 mph becoming south southwest in the afternoon.

    High: 61 °F

    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 33. Southwest wind around 5 mph.

    Low: 33 °F

    Clear

  • M.L.King Day

    M.L.King Day: Sunny, with a high near 65. West southwest wind around 5 mph becoming east in the afternoon.

    High: 65 °F

    Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 39. Northeast wind around 5 mph.

    Low: 39 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 58. North northeast wind around 5 mph becoming east southeast in the afternoon.

    High: 58 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Cloudy, with a low around 50. South southeast wind around 5 mph.

    Low: 50 °F

    Cloudy then
    Slight Chance
    Showers

  • Wednesday

    Wednesday: A 30 percent chance of showers. Mostly cloudy, with a high near 64. South wind around 5 mph.

    High: 64 °F

    Chance
    Showers

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 49. South southeast wind around 5 mph becoming north after midnight.

    Low: 49 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Clear, with a low around 29. Northwest wind around 5 mph.
Sunday
Sunny, with a high near 61. Northwest wind around 5 mph becoming south southwest in the afternoon.
Sunday Night
Clear, with a low around 33. Southwest wind around 5 mph.
M.L.King Day
Sunny, with a high near 65. West southwest wind around 5 mph becoming east in the afternoon.
Monday Night
Mostly cloudy, with a low around 39. Northeast wind around 5 mph.
Tuesday
Mostly cloudy, with a high near 58. North northeast wind around 5 mph becoming east southeast in the afternoon.
Tuesday Night
A 20 percent chance of showers after midnight. Cloudy, with a low around 50. South southeast wind around 5 mph.
Wednesday
A 30 percent chance of showers. Mostly cloudy, with a high near 64. South wind around 5 mph.
Wednesday Night
Mostly cloudy, with a low around 49. South southeast wind around 5 mph becoming north after midnight.
Thursday
Mostly sunny, with a high near 64.
Thursday Night
Partly cloudy, with a low around 45.
Friday
Mostly cloudy, with a high near 68.
Friday Night
Mostly cloudy, with a low around 54.
Saturday
Partly sunny, with a high near 71.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
10:32 pm CST Jan 17, 2026
Forecast Valid:
11pm CST Jan 17, 2026-6pm CST Jan 24, 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