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

Late January Extreme Cold; Watching for Another East Coast Storm Threat This Weekend

Well below normal temperatures will continue for the eastern half of the Lower 48 this week. Another blast of arctic air will spread from the Plains through the East/Southeast Friday into Saturday with more record lows expected even into Florida. Forecasts are being monitored for increasing potential of another significant winter storm to impact the eastern United States this coming weekend. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

45°F

7°C

Humidity 46%
Wind Speed SW 10 mph
Barometer 30.48 in (1032.4 mb)
Dewpoint 25°F (-4°C)
Visibility 10.00 mi
Wind Chill40°F (4°C)
Last update 27 Jan 12:56 pm CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Partly sunny, with a high near 49. South southwest wind around 5 mph.

    High: 49 °F

    Partly Sunny

  • Tonight

    Tonight: Mostly cloudy, then gradually becoming clear, with a low around 27. Calm wind becoming northwest around 5 mph after midnight.

    Low: 27 °F

    Decreasing
    Clouds

  • Wednesday

    Wednesday: Sunny, with a high near 54. West northwest wind around 5 mph becoming north in the afternoon.

    High: 54 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 31. North northeast wind around 5 mph becoming calm.

    Low: 31 °F

    Partly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 64. Light southwest wind becoming south southwest 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 64 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 33. West northwest wind 5 to 15 mph becoming north after midnight. Winds could gust as high as 20 mph.

    Low: 33 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 51. North wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 51 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 28. North wind around 10 mph.

    Low: 28 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 43. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 43 °F

    Sunny

Detailed Forecast

This Afternoon
Partly sunny, with a high near 49. South southwest wind around 5 mph.
Tonight
Mostly cloudy, then gradually becoming clear, with a low around 27. Calm wind becoming northwest around 5 mph after midnight.
Wednesday
Sunny, with a high near 54. West northwest wind around 5 mph becoming north in the afternoon.
Wednesday Night
Partly cloudy, with a low around 31. North northeast wind around 5 mph becoming calm.
Thursday
Partly sunny, with a high near 64. Light southwest wind becoming south southwest 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Thursday Night
Mostly cloudy, with a low around 33. West northwest wind 5 to 15 mph becoming north after midnight. Winds could gust as high as 20 mph.
Friday
Mostly sunny, with a high near 51. North wind 10 to 15 mph, with gusts as high as 25 mph.
Friday Night
Mostly clear, with a low around 28. North wind around 10 mph.
Saturday
Sunny, with a high near 43. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Mostly clear, with a low around 22.
Sunday
Sunny, with a high near 52.
Sunday Night
Mostly clear, with a low around 32.
Monday
Sunny, with a high near 61.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
12:44 pm CST Jan 27, 2026
Forecast Valid:
1pm CST Jan 27, 2026-6pm CST Feb 2, 2026
 
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Additional Resources

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Chance of Precipitation