Weather in San Marcos, TX
Updated 2026-09-26 10:00 local time · ZIP codes 78666
Cloudy
No government weather alerts were returned for this location at the latest update.
Next hours
79°15% rain
83°13% rain86°11% rain86°10% rain88°10% rain91°9% rain
92°1% rain
93°3% rain92°1% rain88°0% rain
86°1% rain83°1% rain3-day weather forecast
Weather details
Sunrise, sunset and moon
Key weather changes ahead
Weather insights for today
Rain chance stays relatively low over the next 12 hours (up to 15%).
It feels like 82°F with winds near 8 mph.
86°F, 1% rain chance and 10 mph wind.
Visibility is around 6 mi; gusts may reach 20 mph.
Current temperature is 79°F, wind 8 mph, rain chance up to 15%.
UV index is 2.
Local weather characteristics in San Marcos
Texas spans several climate zones, from humid Gulf Coast areas to dry western deserts and the High Plains. Heat, severe thunderstorms, tropical systems and winter cold outbreaks can all affect different parts of the state.
San Marcos is part of the South weather region. The forecast point is near 29.88°N latitude and 97.94°W longitude. Local temperature, wind and precipitation can still differ from nearby places, especially where terrain, coastlines or urban development create small-scale weather changes.
San Marcos weather today
Cloudy and 79°F in San Marcos, TX. Today's high is 93°F with a 9% rain chance. Winds are around 8 mph with gusts near 9 mph. Relative humidity is 70%, pressure is 30.02 inHg, and visibility is about 6 miles.
Tonight and tomorrow in San Marcos
Sunrise is at 07:22 AM and sunset is at 07:23 PM. Tomorrow's forecast calls for Overcast with a high near 93°F and a low near 73°F. The maximum rain chance is 11%.