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

Heavy Rain and Thunderstorms in the Plains; Snow in the Northern Rockies; Heavy Rain in Guam

A storm system moving over the Rockies today will bring marginal risks for excessive rainfall and severe thunderstorms from parts of New Mexico into western South Dakota. Heavy snow expected from northwestern Wyoming into southern Montana. Ongoing heavy showers and thunderstorms from Invest 96W could result in localized flash flooding, particularly in central or southern Guam early this morning. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

84°F

29°C

Humidity 48%
Wind Speed N 6 mph
Barometer 30.08 in (1017.7 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Heat Index85°F (29°C)
Last update 15 Oct 10:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 91. East northeast wind around 5 mph.

    High: 91 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 61. East northeast wind around 5 mph becoming calm in the evening.

    Low: 61 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 88. Calm wind becoming south southeast around 5 mph in the afternoon.

    High: 88 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 64. Southeast wind around 5 mph becoming calm after midnight.

    Low: 64 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 90. Light east southeast wind becoming south southeast 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 90 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 70. Southeast wind around 5 mph.

    Low: 70 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 93. South southwest wind around 5 mph.

    High: 93 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 66. South wind around 5 mph becoming north northwest after midnight.

    Low: 66 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 90. East northeast wind around 10 mph, with gusts as high as 20 mph.

    High: 90 °F

    Sunny

Detailed Forecast

Today
Sunny, with a high near 91. East northeast wind around 5 mph.
Tonight
Mostly clear, with a low around 61. East northeast wind around 5 mph becoming calm in the evening.
Thursday
Sunny, with a high near 88. Calm wind becoming south southeast around 5 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 64. Southeast wind around 5 mph becoming calm after midnight.
Friday
Sunny, with a high near 90. Light east southeast wind becoming south southeast 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Friday Night
Mostly clear, with a low around 70. Southeast wind around 5 mph.
Saturday
Sunny, with a high near 93. South southwest wind around 5 mph.
Saturday Night
Mostly clear, with a low around 66. South wind around 5 mph becoming north northwest after midnight.
Sunday
Sunny, with a high near 90. East northeast wind around 10 mph, with gusts as high as 20 mph.
Sunday Night
Clear, with a low around 61.
Monday
Sunny, with a high near 92.
Monday Night
Mostly clear, with a low around 67.
Tuesday
Mostly sunny, with a high near 89.
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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:
6:44 am CDT Oct 15, 2025
Forecast Valid:
11am CDT Oct 15, 2025-6pm CDT Oct 21, 2025
 
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