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

Severe Thunderstorms, Heavy Rain, And Flash Flooding Likely Over The Central U.S.

Strong to severe thunderstorms capable of damaging winds, large hail, and a few tornadoes will be likely this afternoon into tonight over portions of the Plains to the Midwest. Heavy rainfall will lead to flash flooding, some locally significant from Kansas to Missouri. Across the eastern U.S., much above normal temperatures can be expected. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Mostly Cloudy

32°C

89°F

Humidity 59%
Wind Speed SE 17 G 41 km/h
Barometer 1017.1 mb (30.07 in)
Dewpoint 23°C (73°F)
Visibility 16 km
Heat Index36°C (97°F)
Last update 21 Sep 11:56 am CDT
Extended Forecast for

4 Miles SSW San Marcos TX

  • This
    Afternoon

    This Afternoon: A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 36. Heat index values as high as 42. South southeast wind around 20 km/h.

    Chance
    T-storms

    High: 36 °C

  • Tonight

    Tonight: A 20 percent chance of showers after 1am. Mostly cloudy, with a low around 21. Southeast wind 10 to 20 km/h.

    Mostly Cloudy
    then Slight
    Chance
    Showers

    Low: 21 °C

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 36. Heat index values as high as 41. South southeast wind 10 to 15 km/h.

    Partly Sunny
    then Slight
    Chance
    T-storms

    High: 36 °C

  • Sunday
    Night

    Sunday Night: Partly cloudy, with a low around 22. Southeast wind 10 to 15 km/h.

    Partly Cloudy

    Low: 22 °C

  • Monday

    Monday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 36. South wind 10 to 15 km/h.

    Slight Chance
    T-storms

    High: 36 °C

  • Monday
    Night

    Monday Night: Partly cloudy, with a low around 22. Southeast wind 10 to 15 km/h.

    Partly Cloudy

    Low: 22 °C

  • Tuesday

    Tuesday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 34. South wind 10 to 15 km/h.

    Slight Chance
    T-storms

    High: 34 °C

  • Tuesday
    Night

    Tuesday Night: A 20 percent chance of showers and thunderstorms. Mostly clear, with a low around 21. South wind 10 to 15 km/h.

    Slight Chance
    T-storms

    Low: 21 °C

  • Wednesday

    Wednesday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 34. South wind 10 to 15 km/h.

    Slight Chance
    T-storms

    High: 34 °C

Detailed Forecast

This Afternoon
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 36. Heat index values as high as 42. South southeast wind around 20 km/h.
Tonight
A 20 percent chance of showers after 1am. Mostly cloudy, with a low around 21. Southeast wind 10 to 20 km/h.
Sunday
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 36. Heat index values as high as 41. South southeast wind 10 to 15 km/h.
Sunday Night
Partly cloudy, with a low around 22. Southeast wind 10 to 15 km/h.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 36. South wind 10 to 15 km/h.
Monday Night
Partly cloudy, with a low around 22. Southeast wind 10 to 15 km/h.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 34. South wind 10 to 15 km/h.
Tuesday Night
A 20 percent chance of showers and thunderstorms. Mostly clear, with a low around 21. South wind 10 to 15 km/h.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 34. South wind 10 to 15 km/h.
Wednesday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 21.
Thursday
A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 34.
Thursday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 22.
Friday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 34.
Click Map For Forecast
Disclaimer
Map Legend
Point Forecast:
4 Miles SSW San Marcos TX
 29.83°N 97.94°W (Elev. 186 m)
Last Update:
6:09 am CDT Sep 21, 2019
Forecast Valid:
12pm CDT Sep 21, 2019-6pm CDT Sep 27, 2019
 
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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