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

Tracking Atmospheric River in the Northwest U.S. and Clipper with Winter Weather in the Northeast U.S.

A prolonged atmospheric river will continue to bring gusty winds, heavy rainfall which may lead to urban and river flooding with possible landslides, and heavy inter-mountain snow over the Pacific Northwest into the northern Rockies through Thursday. A clipper will cross the Great Lakes and Northeast U.S. into Thursday with areas of moderate to heavy snow and mixed wintry precipitation. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

62°F

17°C

Humidity 67%
Wind Speed Calm
Barometer 30.03 in (1016.7 mb)
Dewpoint 51°F (11°C)
Visibility 10.00 mi
Last update 10 Dec 9:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 72. West wind 5 to 15 mph becoming north northeast in the afternoon. Winds could gust as high as 30 mph.

    High: 72 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 40. North wind 5 to 10 mph, with gusts as high as 25 mph.

    Low: 40 °F

    Clear

  • Thursday

    Thursday: Sunny, with a high near 69. North wind around 5 mph becoming south southeast in the afternoon.

    High: 69 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 50. Southwest wind around 5 mph.

    Low: 50 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 75. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 75 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 58. South wind around 5 mph becoming calm.

    Low: 58 °F

    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 77. North wind around 5 mph becoming south in the morning.

    High: 77 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 57. Southeast wind around 5 mph becoming north northeast after midnight.

    Low: 57 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly cloudy, with a high near 66. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 66 °F

    Mostly Cloudy

Detailed Forecast

Today
Sunny, with a high near 72. West wind 5 to 15 mph becoming north northeast in the afternoon. Winds could gust as high as 30 mph.
Tonight
Clear, with a low around 40. North wind 5 to 10 mph, with gusts as high as 25 mph.
Thursday
Sunny, with a high near 69. North wind around 5 mph becoming south southeast in the afternoon.
Thursday Night
Mostly clear, with a low around 50. Southwest wind around 5 mph.
Friday
Mostly sunny, with a high near 75. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Mostly cloudy, with a low around 58. South wind around 5 mph becoming calm.
Saturday
Partly sunny, with a high near 77. North wind around 5 mph becoming south in the morning.
Saturday Night
Partly cloudy, with a low around 57. Southeast wind around 5 mph becoming north northeast after midnight.
Sunday
Mostly cloudy, with a high near 66. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Sunday Night
Mostly cloudy, with a low around 49.
Monday
Cloudy, with a high near 63.
Monday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 53.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 69.
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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:
10:32 am CST Dec 10, 2025
Forecast Valid:
10am CST Dec 10, 2025-6pm CST Dec 16, 2025
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation