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

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

The next blast of Arctic air surges south down the Plains, across the Great Lakes and through the Southeast and East Friday through Saturday. This could be longest duration of cold in several decades. Forecast models are being closely monitored for potential of another significant winter storm to impact the eastern United States this coming weekend. Confidence in coastal impacts has increased. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

32°F

0°C

Humidity 82%
Wind Speed Calm
Barometer 30.41 in (1030.3 mb)
Dewpoint 27°F (-3°C)
Visibility 3.00 mi
Last update 27 Jan 9:56 pm CST
Extended Forecast for

San Marcos Municipal Airport TX

  • Tonight

    Tonight: Clear, with a low around 25. Calm wind becoming west northwest around 5 mph.

    Low: 25 °F

    Clear

  • Wednesday

    Wednesday: Sunny, with a high near 55. Northwest wind around 5 mph becoming north northeast in the afternoon.

    High: 55 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 28. North northeast wind around 5 mph becoming calm.

    Low: 28 °F

    Partly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 64. Light southwest wind increasing to 5 to 10 mph in the morning.

    High: 64 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 31. West northwest wind 5 to 15 mph becoming north after midnight. Winds could gust as high as 20 mph.

    Low: 31 °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 25. North wind around 10 mph.

    Low: 25 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 44. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 44 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 20. Northeast wind around 5 mph becoming calm in the evening.

    Low: 20 °F

    Mostly Clear

Detailed Forecast

Tonight
Clear, with a low around 25. Calm wind becoming west northwest around 5 mph.
Wednesday
Sunny, with a high near 55. Northwest wind around 5 mph becoming north northeast in the afternoon.
Wednesday Night
Partly cloudy, with a low around 28. North northeast wind around 5 mph becoming calm.
Thursday
Partly sunny, with a high near 64. Light southwest wind increasing to 5 to 10 mph in the morning.
Thursday Night
Mostly cloudy, with a low around 31. 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 25. North wind around 10 mph.
Saturday
Sunny, with a high near 44. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Mostly clear, with a low around 20. Northeast wind around 5 mph becoming calm in the evening.
Sunday
Sunny, with a high near 52.
Sunday Night
Mostly clear, with a low around 30.
Monday
Sunny, with a high near 62.
Monday Night
Partly cloudy, with a low around 41.
Tuesday
A 20 percent chance of showers. Mostly cloudy, with a high near 64.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
10:32 pm CST Jan 27, 2026
Forecast Valid:
10pm CST Jan 27, 2026-6pm CST Feb 3, 2026
 
Forecast Discussion
 
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Additional Resources

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