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.

Overcast

74°F

23°C

Humidity 82%
Wind Speed SE 8 mph
Barometer 29.98 in (1014.4 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Last update 4 Apr 1:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: A 40 percent chance of showers and thunderstorms, mainly after 4am. Cloudy, with a low around 69. South southeast wind around 10 mph.

    Low: 69 °F

    Chance
    Showers

  • Saturday

    Saturday: Showers and thunderstorms likely before 1pm, then showers and possibly a thunderstorm between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Temperature rising to near 75 by noon, then falling to around 65 during the remainder of the day. South southeast wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.

    High: 75 °F⇓

    Showers

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms before 1am, then a slight chance of showers after 4am. Mostly cloudy, with a low around 53. North northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 30%.

    Low: 53 °F

    Chance
    Showers

  • Sunday

    Sunday: A 20 percent chance of showers before 1pm. Mostly cloudy, with a high near 65. North northeast wind around 15 mph, with gusts as high as 30 mph.

    High: 65 °F

    Slight Chance
    Showers

  • Sunday Night

    Sunday Night: A 20 percent chance of showers before 1am. Cloudy, with a low around 53. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 53 °F

    Slight Chance
    Showers

  • Monday

    Monday: Partly sunny, with a high near 70. Northeast wind 5 to 10 mph.

    High: 70 °F

    Partly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 51. East northeast wind around 5 mph becoming calm in the evening.

    Low: 51 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 69. East wind around 5 mph.

    High: 69 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 52. East wind around 5 mph becoming calm in the evening.

    Low: 52 °F

    Mostly Cloudy

Detailed Forecast

Overnight
A 40 percent chance of showers and thunderstorms, mainly after 4am. Cloudy, with a low around 69. South southeast wind around 10 mph.
Saturday
Showers and thunderstorms likely before 1pm, then showers and possibly a thunderstorm between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Temperature rising to near 75 by noon, then falling to around 65 during the remainder of the day. South southeast wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.
Saturday Night
A chance of showers and thunderstorms before 1am, then a slight chance of showers after 4am. Mostly cloudy, with a low around 53. North northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 30%.
Sunday
A 20 percent chance of showers before 1pm. Mostly cloudy, with a high near 65. North northeast wind around 15 mph, with gusts as high as 30 mph.
Sunday Night
A 20 percent chance of showers before 1am. Cloudy, with a low around 53. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Partly sunny, with a high near 70. Northeast wind 5 to 10 mph.
Monday Night
Mostly cloudy, with a low around 51. East northeast wind around 5 mph becoming calm in the evening.
Tuesday
Mostly cloudy, with a high near 69. East wind around 5 mph.
Tuesday Night
Mostly cloudy, with a low around 52. East wind around 5 mph becoming calm in the evening.
Wednesday
Partly sunny, with a high near 78.
Wednesday Night
Mostly cloudy, with a low around 58.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 82.
Thursday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 65.
Friday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 82.
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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:
1:24 am CDT Apr 4, 2026
Forecast Valid:
2am CDT Apr 4, 2026-6pm CDT Apr 10, 2026
 
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