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San Marcos, TX Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for San Marcos, a city in Hays County, Texas.

Tonight
52°F
Mostly Clear
Mostly clear, with a low around 52. North wind around 5 mph.

7-day forecast for San Marcos

WhenTempForecastWindPrecip
Tonight 52°F Mostly Clear 5 mph N 0%
Wednesday 74°F Sunny 0 to 5 mph NNE 0%
Wednesday Night 52°F Mostly Clear 0 mph 0%
Thursday 79°F Mostly Sunny 0 to 5 mph S 3%
Thursday Night 57°F Partly Cloudy 0 to 15 mph WNW 11%
Friday 73°F Sunny 5 to 15 mph N 0%
Friday Night 52°F Partly Cloudy 5 to 10 mph N 2%
Saturday 68°F Slight Chance Rain Showers 5 to 10 mph N 17%
Saturday Night 50°F Partly Cloudy 5 to 10 mph N 13%
Sunday 69°F Mostly Sunny 5 to 10 mph N 7%
Sunday Night 47°F Mostly Clear 0 to 5 mph NNW 8%
Monday 71°F Sunny 0 to 5 mph NE 4%
Monday Night 48°F Mostly Clear 0 mph 1%
Tuesday 73°F Mostly Sunny 0 to 5 mph SSW 3%

Forecast source: National Weather Service (api.weather.gov) for San Marcos (29.872, -97.936). Updated through the day.

Growing snapshot for San Marcos

Last spring frost
Feb 28
First fall frost
Nov 29
Growing season
273 days
Hardiness zone
9a

More local growing data for San Marcos: nearby ZIP 78666 weather · frost dates · planting calendar · Texas frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, San Marcos, Tx (2.1 mi from San Marcos). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.