Current conditions at
San Marcos, San Marcos Municipal Airport (KHYI)
Lat: 29.89°NLon: 97.86°WElev: 597ft.
Fair
82°F
28°C
| Humidity | 77% |
| Wind Speed | SE 16 G 20 mph |
| Barometer | 29.87 in (1010.8 mb) |
| Dewpoint | 74°F (23°C) |
| Visibility | 10.00 mi |
| Heat Index | 88°F (31°C) |
| Last update | 18 May 8:56 pm CDT |
Extended Forecast for
San Marcos TX
Tonight
Low: 77 °F
Mostly Cloudy
Tuesday
High: 89 °F
Mostly Cloudy
then Slight
Chance
T-stormsTuesday Night
Low: 71 °F
Heavy Rain
Wednesday
High: 84 °F
Chance
T-storms then
Showers
LikelyWednesday Night
Low: 72 °F
Showers
LikelyThursday
High: 81 °F
Showers then
T-stormsThursday Night
Low: 70 °F
Showers
LikelyFriday
High: 83 °F
Chance
T-storms then
Showers
LikelyFriday Night
Low: 71 °F
Chance
T-storms
Detailed Forecast
Tonight
Mostly cloudy, with a low around 77. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday
A 20 percent chance of showers and thunderstorms after 4pm. Cloudy, then gradually becoming mostly sunny, with a high near 89. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A slight chance of showers and thunderstorms before 7pm, then showers likely and possibly a thunderstorm between 7pm and 1am, then a chance of showers and thunderstorms after 1am. Some of the storms could produce heavy rainfall. Mostly cloudy, with a low around 71. Southeast wind 5 to 15 mph becoming east northeast after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 70%. New rainfall amounts between 1 and 2 inches possible.
Wednesday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 84. Northeast wind around 5 mph becoming south southeast in the afternoon. Chance of precipitation is 60%.
Wednesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 72. East southeast wind around 5 mph. Chance of precipitation is 70%.
Thursday
Showers and possibly a thunderstorm. High near 81. Light south southeast wind becoming southeast 5 to 10 mph in the morning. Chance of precipitation is 90%.
Thursday Night
Showers likely and possibly a thunderstorm before 1am, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 70. South southeast wind around 5 mph becoming calm in the evening. Chance of precipitation is 70%.
Friday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 83. South wind around 5 mph. Chance of precipitation is 60%.
Friday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Southeast wind around 5 mph becoming calm in the evening.
Saturday
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1pm. High near 82. Chance of precipitation is 80%.
Saturday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 70. Chance of precipitation is 60%.
Sunday
Showers and thunderstorms likely. Mostly cloudy, with a high near 83. Chance of precipitation is 70%.
Sunday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70.
Memorial Day
A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 84.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
San Marcos TX
29.88°N 97.94°W (Elev. 577 ft)
29.88°N 97.94°W (Elev. 577 ft)
6:42 pm CDT May 18, 2026
8pm CDT May 18, 2026-6pm CDT May 25, 2026
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