Flooding Threat in Parts of Texas and New Mexico; Heat in the Western U.S.

Heavy to excessive rainfall across parts of central Texas into southern New Mexico may bring areas of flooding into this evening. Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Hot temperatures are forecast for the far southwest U.S., parts of California, and the interior northwest U.S. this week. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

A Few Clouds

88°F

31°C

Humidity 55%
Wind Speed NE 13 mph
Barometer 29.97 in (1014.1 mb)
Dewpoint 70°F (21°C)
Visibility 9.00 mi
Heat Index93°F (34°C)
Last update 31 Aug 5:56 pm CDT
Extended Forecast for

San Marcos TX

Flood Watch until September 1, 12:00pm
Click here for hazard details and duration
Flood Watch
  •  
    Flood Watch until September 1, 12:00pm

    NOW until 12:00pm Mon

    Flood Watch

  • Tonight

    Low: 73 °F

    Chance
    T-storms

  • Labor Day

    Labor Day: A chance of showers, with thunderstorms also possible after 10am.  Partly sunny, with a high near 88. Calm wind becoming north northeast around 5 mph in the afternoon.  Chance of precipitation is 50%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 88 °F

    Chance
    Showers then
    Chance
    T-storms

  • Monday Night

    Monday Night: Partly cloudy, with a low around 72. East northeast wind around 5 mph becoming calm  in the evening.

    Low: 72 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 93. Calm wind becoming north northeast around 5 mph in the morning.

    High: 93 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 71. Northeast wind around 5 mph becoming calm  in the evening.

    Low: 71 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 95. North wind around 5 mph.

    High: 95 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 69. Northeast wind around 5 mph becoming calm  in the evening.

    Low: 69 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 96. Calm wind becoming south southwest around 5 mph.

    High: 96 °F

    Sunny

Detailed Forecast

Tonight
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 73. Northeast wind 5 to 10 mph becoming light and variable after midnight. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Labor Day
A chance of showers, with thunderstorms also possible after 10am. Partly sunny, with a high near 88. Calm wind becoming north northeast around 5 mph in the afternoon. Chance of precipitation is 50%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Monday Night
Partly cloudy, with a low around 72. East northeast wind around 5 mph becoming calm in the evening.
Tuesday
Sunny, with a high near 93. Calm wind becoming north northeast around 5 mph in the morning.
Tuesday Night
Mostly clear, with a low around 71. Northeast wind around 5 mph becoming calm in the evening.
Wednesday
Sunny, with a high near 95. North wind around 5 mph.
Wednesday Night
Mostly clear, with a low around 69. Northeast wind around 5 mph becoming calm in the evening.
Thursday
Sunny, with a high near 96. Calm wind becoming south southwest around 5 mph.
Thursday Night
Partly cloudy, with a low around 72. South southwest wind around 5 mph.
Friday
Mostly sunny, with a high near 95.
Friday Night
Mostly cloudy, with a low around 72.
Saturday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 91.
Saturday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 72.
Sunday
A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 90.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
6:06 pm CDT Aug 31, 2025
6pm CDT Aug 31, 2025-6pm CDT Sep 7, 2025
 
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Additional Resources

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