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

Prolonged Atmospheric River in the Pacific Northwest; Snow and High Winds in the North-Central U.S.

A prolonged atmospheric river will continue impacting the Pacific Northwest with heavy rainfall which has lead to areas of urban and river flooding along with gusty winds into Thursday. A clipper will bring heavy snow, some mixed wintry precipitation, and gusty to high winds across the northern Plains, Upper Midwest, and the Great Lakes into Thursday morning. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

68°F

20°C

Humidity 25%
Wind Speed S 12 mph
Barometer 30.04 in (1017.2 mb)
Dewpoint 31°F (-1°C)
Visibility 10.00 mi
Last update 9 Dec 3:56 pm CST
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Mostly clear, with a low around 45. South southwest wind 5 to 10 mph.

    Low: 45 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 71. Southwest wind 5 to 10 mph becoming north northeast in the afternoon.

    High: 71 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 43. North wind 5 to 10 mph.

    Low: 43 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 70. North wind around 5 mph becoming south in the afternoon.

    High: 70 °F

    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 52. South southwest wind around 5 mph.

    Low: 52 °F

    Partly Cloudy

  • Friday

    Friday: Partly sunny, with a high near 76. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 76 °F

    Partly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 59. South wind around 5 mph.

    Low: 59 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 78. South wind 5 to 10 mph.

    High: 78 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 55. South wind 5 to 10 mph becoming north northeast after midnight.

    Low: 55 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly clear, with a low around 45. South southwest wind 5 to 10 mph.
Wednesday
Sunny, with a high near 71. Southwest wind 5 to 10 mph becoming north northeast in the afternoon.
Wednesday Night
Mostly clear, with a low around 43. North wind 5 to 10 mph.
Thursday
Sunny, with a high near 70. North wind around 5 mph becoming south in the afternoon.
Thursday Night
Partly cloudy, with a low around 52. South southwest wind around 5 mph.
Friday
Partly sunny, with a high near 76. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Partly cloudy, with a low around 59. South wind around 5 mph.
Saturday
Partly sunny, with a high near 78. South wind 5 to 10 mph.
Saturday Night
Partly cloudy, with a low around 55. South wind 5 to 10 mph becoming north northeast after midnight.
Sunday
Mostly cloudy, with a high near 65.
Sunday Night
Mostly cloudy, with a low around 46.
Monday
A 20 percent chance of showers. Mostly cloudy, with a high near 65.
Monday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 49.
Tuesday
A 20 percent chance of showers. Mostly cloudy, with a high near 65.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.9°N 97.91°W (Elev. 640 ft)
Last Update:
4:32 pm CST Dec 9, 2025
Forecast Valid:
4pm CST Dec 9, 2025-6pm CST Dec 16, 2025
 
Forecast Discussion
 
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Additional Resources

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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