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

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

100°F

38°C

Humidity 37%
Wind Speed S 9 mph
Barometer 29.94 in (1012.8 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Heat Index107°F (42°C)
Last update 2 Sep 1:56 pm CDT
Extended Forecast for

4 Miles S Lockhart TX

  • This Afternoon

    This Afternoon: Sunny and hot, with a high near 100. Heat index values as high as 105. South wind around 5 mph.

    High: 100 °F

    Hot

  • Tonight

    Tonight: Mostly clear, with a low around 76. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Mostly Clear

  • Thursday

    Thursday: A 20 percent chance of showers and thunderstorms after 4pm. Sunny and hot, with a high near 100. Heat index values as high as 106. South southwest wind 5 to 10 mph.

    High: 100 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers and thunderstorms after 1am. Increasing clouds, with a low around 76. South wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

    Low: 76 °F

    Slight Chance
    T-storms

  • Friday

    Friday: A slight chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 98. South southeast wind around 5 mph. Chance of precipitation is 20%.

    High: 98 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

  • Friday Night

    Friday Night: Mostly clear, with a low around 74. East southeast wind 5 to 10 mph becoming light south after midnight.

    Low: 74 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 98. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 98 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 74. Southeast wind 5 to 10 mph becoming light south in the evening.

    Low: 74 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 97. Calm wind becoming east southeast around 5 mph in the afternoon.

    High: 97 °F

    Sunny

Detailed Forecast

This Afternoon
Sunny and hot, with a high near 100. Heat index values as high as 105. South wind around 5 mph.
Tonight
Mostly clear, with a low around 76. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday
A 20 percent chance of showers and thunderstorms after 4pm. Sunny and hot, with a high near 100. Heat index values as high as 106. South southwest wind 5 to 10 mph.
Thursday Night
A slight chance of showers and thunderstorms before 7pm, then a slight chance of showers and thunderstorms after 1am. Increasing clouds, with a low around 76. South wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Friday
A slight chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 98. South southeast wind around 5 mph. Chance of precipitation is 20%.
Friday Night
Mostly clear, with a low around 74. East southeast wind 5 to 10 mph becoming light south after midnight.
Saturday
Mostly sunny, with a high near 98. Calm wind becoming southeast around 5 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 74. Southeast wind 5 to 10 mph becoming light south in the evening.
Sunday
Sunny, with a high near 97. Calm wind becoming east southeast around 5 mph in the afternoon.
Sunday Night
Mostly clear, with a low around 75.
Labor Day
Sunny, with a high near 97.
Monday Night
Mostly clear, with a low around 74.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 96.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles S Lockhart TX
 29.82°N 97.68°W (Elev. 548 ft)
Last Update:
1:36 pm CDT Sep 2, 2026
Forecast Valid:
2pm CDT Sep 2, 2026-6pm CDT Sep 8, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation