Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

70°F

21°C

Humidity 90%
Wind Speed S 3 mph
Barometer 29.84 in (1009.6 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Last update 18 Apr 4:56 am CDT
Extended Forecast for

3 Miles WSW San Marcos TX

  • Today

    Today: A chance of showers and thunderstorms between 7am and 4pm, then showers likely and possibly a thunderstorm after 4pm.  Cloudy, with a temperature rising to near 73 by 10am, then falling to around 65 during the remainder of the day. South wind 5 to 10 mph becoming north 15 to 20 mph in the afternoon. Winds could gust as high as 30 mph.  Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 73 °F

    Showers
    Likely

  • Tonight

    Tonight: Showers and thunderstorms likely, mainly before 1am.  Mostly cloudy, with a low around 53. North northeast wind 15 to 20 mph, with gusts as high as 35 mph.  Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 53 °F

    Showers
    Likely

  • Sunday

    Sunday: Partly sunny, with a high near 71. North northeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 71 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 55. East wind around 5 mph becoming calm  in the evening.

    Low: 55 °F

    Mostly Cloudy

  • Monday

    Monday: A 50 percent chance of showers and thunderstorms.  Cloudy, with a high near 67. East northeast wind around 5 mph.

    High: 67 °F

    Chance
    T-storms

  • Monday Night

    Monday Night: A 50 percent chance of showers and thunderstorms.  Cloudy, with a low around 57. East wind around 5 mph.

    Low: 57 °F

    Chance
    T-storms

  • Tuesday

    Tuesday: A 50 percent chance of showers and thunderstorms.  Cloudy, with a high near 71. East wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 71 °F

    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers and thunderstorms before 1am.  Cloudy, with a low around 63. Southeast wind 5 to 10 mph.

    Low: 63 °F

    Slight Chance
    T-storms

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms, mainly after 1pm.  Cloudy, with a high near 81. Southeast wind 5 to 10 mph.

    High: 81 °F

    Chance
    T-storms

Detailed Forecast

Today
A chance of showers and thunderstorms between 7am and 4pm, then showers likely and possibly a thunderstorm after 4pm. Cloudy, with a temperature rising to near 73 by 10am, then falling to around 65 during the remainder of the day. South wind 5 to 10 mph becoming north 15 to 20 mph in the afternoon. Winds could gust as high as 30 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tonight
Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 53. North northeast wind 15 to 20 mph, with gusts as high as 35 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Sunday
Partly sunny, with a high near 71. North northeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly cloudy, with a low around 55. East wind around 5 mph becoming calm in the evening.
Monday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 67. East northeast wind around 5 mph.
Monday Night
A 50 percent chance of showers and thunderstorms. Cloudy, with a low around 57. East wind around 5 mph.
Tuesday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 71. East wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
A 20 percent chance of showers and thunderstorms before 1am. Cloudy, with a low around 63. Southeast wind 5 to 10 mph.
Wednesday
A 30 percent chance of showers and thunderstorms, mainly after 1pm. Cloudy, with a high near 81. Southeast wind 5 to 10 mph.
Wednesday Night
Mostly cloudy, with a low around 67.
Thursday
Mostly cloudy, with a high near 84.
Thursday Night
Mostly cloudy, with a low around 68.
Friday
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 86.
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ABOUT THIS FORECAST

 
Point Forecast:
3 Miles WSW San Marcos TX
 29.86°N 97.97°W (Elev. 646 ft)
5:32 am CDT Apr 18, 2026
5am CDT Apr 18, 2026-6pm CDT Apr 24, 2026
 
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Additional Resources

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