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

41°F

5°C

Humidity 57%
Wind Speed NW 5 mph
Barometer 30.16 in (1021.2 mb)
Dewpoint 27°F (-3°C)
Visibility 10.00 mi
Wind Chill38°F (3°C)
Last update 11 Dec 3:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 68. Calm wind becoming south around 5 mph in the afternoon.

    High: 68 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 49. Southwest wind around 5 mph.

    Low: 49 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 76. Southwest wind around 5 mph becoming south southeast in the afternoon.

    High: 76 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Increasing clouds, with a low around 55. Calm wind becoming north around 5 mph after midnight.

    Low: 55 °F

    Increasing
    Clouds

  • Saturday

    Saturday: Partly sunny, with a high near 72. North wind around 5 mph becoming south southeast in the afternoon.

    High: 72 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 51. East southeast wind 5 to 10 mph becoming north northeast after midnight.

    Low: 51 °F

    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 60. North northeast wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 60 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 41. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 41 °F

    Partly Cloudy

  • Monday

    Monday: Mostly cloudy, with a high near 60. Northeast wind around 5 mph becoming south southeast in the afternoon.

    High: 60 °F

    Mostly Cloudy

Detailed Forecast

Today
Sunny, with a high near 68. Calm wind becoming south around 5 mph in the afternoon.
Tonight
Mostly clear, with a low around 49. Southwest wind around 5 mph.
Friday
Mostly sunny, with a high near 76. Southwest wind around 5 mph becoming south southeast in the afternoon.
Friday Night
Increasing clouds, with a low around 55. Calm wind becoming north around 5 mph after midnight.
Saturday
Partly sunny, with a high near 72. North wind around 5 mph becoming south southeast in the afternoon.
Saturday Night
Partly cloudy, with a low around 51. East southeast wind 5 to 10 mph becoming north northeast after midnight.
Sunday
Partly sunny, with a high near 60. North northeast wind 10 to 15 mph, with gusts as high as 30 mph.
Sunday Night
Partly cloudy, with a low around 41. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Mostly cloudy, with a high near 60. Northeast wind around 5 mph becoming south southeast in the afternoon.
Monday Night
Mostly cloudy, with a low around 48.
Tuesday
Mostly cloudy, with a high near 66.
Tuesday Night
Mostly cloudy, with a low around 56.
Wednesday
Mostly sunny, with a high near 75.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
4:32 am CST Dec 11, 2025
Forecast Valid:
4am CST Dec 11, 2025-6pm CST Dec 17, 2025
 
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