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

Areas of Severe Thunderstorms and Excessive Rainfall Today

Scattered severe thunderstorms are possible across parts of the Ohio Valley and Mid-Atlantic this afternoon and evening. Strong to severe wind gusts capable of producing wind damage should be the primary hazard, but isolated hail may also occur. Thunderstorms may bring heavy to excessive rainfall and possible flooding today over the northern Gulf Coast and upper Ohio Valley. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

77°F

25°C

Humidity 74%
Wind Speed E 7 mph
Barometer 29.86 in (1010.7 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 27 May 4:56 pm CDT
Extended Forecast for

3 Miles NNW San Marcos Municipal Airport TX

  • Tonight

    Tonight: Partly cloudy, with a low around 66. Southeast wind around 5 mph becoming calm in the evening.

    Low: 66 °F

    Partly Cloudy

  • Thursday

    Thursday: Patchy fog before 9am. Otherwise, sunny, with a high near 87. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 87 °F

    Patchy Fog
    then Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 72. Southeast wind around 5 mph becoming calm in the evening.

    Low: 72 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 88. Calm wind becoming south around 5 mph in the afternoon.

    High: 88 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 73. Southeast wind around 5 mph.

    Low: 73 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 89. South wind 5 to 10 mph.

    High: 89 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 73. South southeast wind around 5 mph.

    Low: 73 °F

    Mostly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 90. South wind around 5 mph.

    High: 90 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 73. Southeast wind 5 to 10 mph becoming light south after midnight.

    Low: 73 °F

    Partly Cloudy

Detailed Forecast

Tonight
Partly cloudy, with a low around 66. Southeast wind around 5 mph becoming calm in the evening.
Thursday
Patchy fog before 9am. Otherwise, sunny, with a high near 87. Calm wind becoming southeast around 5 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 72. Southeast wind around 5 mph becoming calm in the evening.
Friday
Mostly sunny, with a high near 88. Calm wind becoming south around 5 mph in the afternoon.
Friday Night
Partly cloudy, with a low around 73. Southeast wind around 5 mph.
Saturday
Partly sunny, with a high near 89. South wind 5 to 10 mph.
Saturday Night
Mostly cloudy, with a low around 73. South southeast wind around 5 mph.
Sunday
Mostly sunny, with a high near 90. South wind around 5 mph.
Sunday Night
Partly cloudy, with a low around 73. Southeast wind 5 to 10 mph becoming light south after midnight.
Monday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 91.
Monday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 72.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 90.
Tuesday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 71.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 88.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
3 Miles NNW San Marcos Municipal Airport TX
 29.95°N 97.89°W (Elev. 646 ft)
Last Update:
4:52 pm CDT May 27, 2026
Forecast Valid:
5pm CDT May 27, 2026-6pm CDT Jun 3, 2026
 
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