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Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fog/Mist

80°F

27°C

Humidity 87%
Wind Speed S 8 mph
Barometer 29.95 in (1013.1 mb)
Dewpoint 76°F (24°C)
Visibility 5.00 mi
Heat Index85°F (29°C)
Last update 12 Sep 8:56 am CDT
Extended Forecast for

Wimberley TX

Heat Advisory September 12, 12:00pm until September 12, 07:00pm
Click here for hazard details and duration
Heat Advisory

  • Today

    Today: A 20 percent chance of showers and thunderstorms after 4pm. Mostly sunny and hot, with a high near 101. Heat index values as high as 109. South wind 5 to 10 mph.

    High: 101 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Tonight

    Tonight: A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers between 7pm and 8pm. Mostly clear, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

    Low: 75 °F

    Slight Chance
    T-storms then
    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, then gradually becoming sunny and hot, with a high near 99. Heat index values as high as 105. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 99 °F

    Hot

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 75. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny and hot, with a high near 99. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 99 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 75. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 99. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 99 °F

    Hot

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 74. Southeast wind 5 to 10 mph becoming light south after midnight. Winds could gust as high as 20 mph.

    Low: 74 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 97. Calm wind becoming south southeast around 5 mph in the morning.

    High: 97 °F

    Mostly Sunny

Detailed Forecast

Today
A 20 percent chance of showers and thunderstorms after 4pm. Mostly sunny and hot, with a high near 101. Heat index values as high as 109. South wind 5 to 10 mph.
Tonight
A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers between 7pm and 8pm. Mostly clear, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Sunday
Partly sunny, then gradually becoming sunny and hot, with a high near 99. Heat index values as high as 105. South wind 5 to 10 mph, with gusts as high as 20 mph.
Sunday Night
Partly cloudy, with a low around 75. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Mostly sunny and hot, with a high near 99. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Mostly clear, with a low around 75. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Sunny and hot, with a high near 99. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
Mostly clear, with a low around 74. Southeast wind 5 to 10 mph becoming light south after midnight. Winds could gust as high as 20 mph.
Wednesday
Mostly sunny, with a high near 97. Calm wind becoming south southeast around 5 mph in the morning.
Wednesday Night
Mostly clear, with a low around 74.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 96.
Thursday Night
Partly cloudy, with a low around 73.
Friday
Mostly sunny, with a high near 95.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Wimberley TX
 29.99°N 98.1°W (Elev. 817 ft)
Last Update:
8:32 am CDT Sep 12, 2026
Forecast Valid:
9am CDT Sep 12, 2026-6pm CDT Sep 18, 2026
 
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