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

Above Average Temperatures for Most Today; Winter Weather Returns to the Upper Midwest and Great Lakes

Well above average temperatures are forecast today into Wednesday over most of the lower 48 states away from the Gulf Coast. A storm system passing across southern Canada will bring a wintry mix to the upper Great Lakes today. A trailing cold front will then bring the wintry mix from the central Appalachians through the Northeast U.S. Wednesday and Thursday. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

52°F

11°C

Humidity 75%
Wind Speed SW 5 mph
Barometer 30.33 in (1027.1 mb)
Dewpoint 44°F (7°C)
Visibility 10.00 mi
Wind Chill51°F (11°C)
Last update 13 Jan 10:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Cloudy, then gradually becoming mostly sunny, with a high near 63. Southwest wind around 5 mph.

    High: 63 °F

    Decreasing
    Clouds

  • Tonight

    Tonight: Mostly clear, with a low around 46. West southwest wind around 5 mph.

    Low: 46 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 69. West wind 5 to 10 mph becoming north 15 to 20 mph in the morning. Winds could gust as high as 30 mph.

    High: 69 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Clear, with a low around 38. North wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 38 °F

    Clear

  • Thursday

    Thursday: Sunny, with a high near 63. North northwest wind around 5 mph becoming south southeast in the afternoon.

    High: 63 °F

    Sunny

  • Thursday Night

    Thursday Night: Clear, with a low around 43. South wind around 5 mph.

    Low: 43 °F

    Clear

  • Friday

    Friday: Sunny, with a high near 69. Southwest wind 5 to 10 mph becoming north in the afternoon.

    High: 69 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 40. North northeast wind 5 to 10 mph.

    Low: 40 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 61. North northeast wind 5 to 10 mph becoming east in the afternoon.

    High: 61 °F

    Sunny

Detailed Forecast

Today
Cloudy, then gradually becoming mostly sunny, with a high near 63. Southwest wind around 5 mph.
Tonight
Mostly clear, with a low around 46. West southwest wind around 5 mph.
Wednesday
Sunny, with a high near 69. West wind 5 to 10 mph becoming north 15 to 20 mph in the morning. Winds could gust as high as 30 mph.
Wednesday Night
Clear, with a low around 38. North wind 5 to 15 mph, with gusts as high as 25 mph.
Thursday
Sunny, with a high near 63. North northwest wind around 5 mph becoming south southeast in the afternoon.
Thursday Night
Clear, with a low around 43. South wind around 5 mph.
Friday
Sunny, with a high near 69. Southwest wind 5 to 10 mph becoming north in the afternoon.
Friday Night
Mostly clear, with a low around 40. North northeast wind 5 to 10 mph.
Saturday
Sunny, with a high near 61. North northeast wind 5 to 10 mph becoming east in the afternoon.
Saturday Night
Mostly clear, with a low around 38.
Sunday
Sunny, with a high near 66.
Sunday Night
Mostly clear, with a low around 44.
M.L.King Day
Mostly sunny, with a high near 67.
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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:
11:32 am CST Jan 13, 2026
Forecast Valid:
11am CST Jan 13, 2026-6pm CST Jan 19, 2026
 
Forecast Discussion
 
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Additional Resources

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