San Marcos, TX Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for San Marcos, a city in Hays County, Texas.
Today
97°F
Sunny
Sunny, with a high near 97. Heat index values as high as 101. South southeast wind around 5 mph.
7-day forecast for San Marcos
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 97°F | Sunny | 5 mph SSE | 0% |
| Tonight | 73°F | Mostly Clear | 0 to 5 mph S | 0% |
| Sunday | 98°F | Mostly Sunny | 0 to 5 mph S | 0% |
| Sunday Night | 75°F | Partly Cloudy | 0 to 5 mph SSE | 5% |
| Monday | 97°F | Sunny | 0 to 5 mph SSE | 12% |
| Monday Night | 75°F | Mostly Clear | 0 to 5 mph S | 12% |
| Tuesday | 97°F | Slight Chance Rain Showers | 0 to 5 mph NE | 15% |
| Tuesday Night | 75°F | Slight Chance Showers And Thunderstorms | 0 to 5 mph ENE | 19% |
| Wednesday | 97°F | Slight Chance Rain Showers then Mostly Sunny | 0 to 5 mph NE | 18% |
| Wednesday Night | 74°F | Partly Cloudy | 0 to 5 mph E | 7% |
| Thursday | 96°F | Mostly Sunny | 0 to 10 mph ENE | 6% |
| Thursday Night | 72°F | Partly Cloudy | 0 to 10 mph ESE | 4% |
| Friday | 96°F | Mostly Sunny | 0 to 5 mph ENE | 4% |
| Friday Night | 72°F | Partly Cloudy | 0 to 5 mph E | 4% |
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
Bear Creek
Belterra
Buda
Driftwood
Dripping Springs
Kyle
Mountain City
Niederwald
Uhland
Wimberley
Woodcreek
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 Sep 19, 2026.