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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.

Thunderstorm Fog/Mist

70°F

21°C

Humidity 100%
Wind Speed S 15 mph
Barometer 29.90 in (1011.7 mb)
Dewpoint 70°F (21°C)
Visibility 1.50 mi
Last update 12 Jun 2:56 am CDT
Extended Forecast for

San Marcos TX

Flood Watch June 12, 03:55am until June 12, 07:00pm
Flash Flood Warning until June 12, 05:00am
Click here for hazard details and duration
Flood Watch
Flash Flood Warning
  •  
    Flood Watch June 12, 03:55am until June 12, 07:00pm
    Flash Flood Warning until June 12, 05:00am

    NOW: Multiple hazards in effect

    Click HERE for Details

  • Overnight

    Low: 70 °F

    T-storms

  • Thursday

    Thursday: Showers and thunderstorms, mainly before 10am. High near 86. South wind around 5 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

    High: 86 °F

    T-storms then
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A 10 percent chance of showers and thunderstorms before 7pm. Increasing clouds, with a low around 73. South wind around 5 mph.

    Low: 73 °F

    Slight Chance
    T-storms then
    Mostly Cloudy

  • Friday

    Friday: A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 92. Heat index values as high as 106. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 92 °F

    Slight Chance
    T-storms

  • Friday Night

    Friday Night: Partly cloudy, with a low around 75. South southeast wind 5 to 10 mph.

    Low: 75 °F

    Partly Cloudy

  • Saturday

    Saturday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 93. South wind 5 to 10 mph.

    High: 93 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 75. South wind 5 to 10 mph.

    Low: 75 °F

    Partly Cloudy

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 94. South wind 5 to 10 mph.

    High: 94 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

Detailed Forecast

Overnight
Showers and thunderstorms. Low around 70. South southeast wind 5 to 10 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Thursday
Showers and thunderstorms, mainly before 10am. High near 86. South wind around 5 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.
Thursday Night
A 10 percent chance of showers and thunderstorms before 7pm. Increasing clouds, with a low around 73. South wind around 5 mph.
Friday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 92. Heat index values as high as 106. South wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Partly cloudy, with a low around 75. South southeast wind 5 to 10 mph.
Saturday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 93. South wind 5 to 10 mph.
Saturday Night
Partly cloudy, with a low around 75. South wind 5 to 10 mph.
Sunday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 94. South wind 5 to 10 mph.
Sunday Night
Partly cloudy, with a low around 74. South wind 5 to 10 mph.
Monday
Mostly sunny, with a high near 94.
Monday Night
Mostly clear, with a low around 75.
Tuesday
Mostly sunny, with a high near 96.
Tuesday Night
Partly cloudy, with a low around 74.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 95.
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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:
2:42 am CDT Jun 12, 2025
Forecast Valid:
3am CDT Jun 12, 2025-6pm CDT Jun 18, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation