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

Winter Storm Bringing Widespread Hazardous Weather to the Eastern U.S.

A rapidly-intensifying winter storm continues to bring heavy snow, high winds, and blizzard conditions over the Upper Midwest and Great Lakes through today. An Arctic front will lead in a period of gusty to high winds and sharply colder temperatures over the entire eastern U.S. Heavy lake effect snow is then expected from Lakes Erie and Ontario through New Year's Day. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

44°F

7°C

Humidity 34%
Wind Speed N 17 mph
Barometer 30.50 in (1032.6 mb)
Dewpoint 17°F (-8°C)
Visibility 10.00 mi
Wind Chill36°F (2°C)
Last update 29 Dec 1:56 pm CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Cloudy, with a high near 46. North wind around 15 mph, with gusts as high as 30 mph.

    High: 46 °F

    Cloudy

  • Tonight

    Tonight: Cloudy, then gradually becoming partly cloudy, with a low around 38. North wind around 10 mph, with gusts as high as 20 mph.

    Low: 38 °F

    Decreasing
    Clouds

  • Tuesday

    Tuesday: Partly sunny, then gradually becoming sunny, with a high near 58. North wind around 5 mph becoming calm in the afternoon.

    High: 58 °F

    Becoming
    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 35. Calm wind becoming west around 5 mph.

    Low: 35 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 65. South southwest wind 5 to 10 mph.

    High: 65 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 42. South southwest wind around 5 mph.

    Low: 42 °F

    Partly Cloudy

  • New Year's Day

    New Year's Day: Partly sunny, with a high near 72. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 72 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 55. South southwest wind 5 to 10 mph.

    Low: 55 °F

    Partly Cloudy

  • Friday

    Friday: Sunny, with a high near 84. Southwest wind around 10 mph, with gusts as high as 20 mph.

    High: 84 °F

    Sunny

Detailed Forecast

This Afternoon
Cloudy, with a high near 46. North wind around 15 mph, with gusts as high as 30 mph.
Tonight
Cloudy, then gradually becoming partly cloudy, with a low around 38. North wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Partly sunny, then gradually becoming sunny, with a high near 58. North wind around 5 mph becoming calm in the afternoon.
Tuesday Night
Mostly clear, with a low around 35. Calm wind becoming west around 5 mph.
Wednesday
Sunny, with a high near 65. South southwest wind 5 to 10 mph.
Wednesday Night
Partly cloudy, with a low around 42. South southwest wind around 5 mph.
New Year's Day
Partly sunny, with a high near 72. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Partly cloudy, with a low around 55. South southwest wind 5 to 10 mph.
Friday
Sunny, with a high near 84. Southwest wind around 10 mph, with gusts as high as 20 mph.
Friday Night
Clear, with a low around 53.
Saturday
Sunny, with a high near 76.
Saturday Night
Mostly clear, with a low around 49.
Sunday
Sunny, with a high near 77.
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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:
1:46 pm CST Dec 29, 2025
Forecast Valid:
2pm CST Dec 29, 2025-6pm CST Jan 4, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation