St. Marys, KS Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. Marys, a city in Pottawatomie County, Kansas.
Overnight
44°F
Mostly Cloudy
Mostly cloudy, with a low around 44. Northwest wind around 10 mph.
7-day forecast for St. Marys
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 44°F | Mostly Cloudy | 10 mph NW | 0% |
| Wednesday | 57°F | Partly Sunny | 5 to 10 mph W | 0% |
| Wednesday Night | 39°F | Clear | 5 mph W | 0% |
| Thursday | 57°F | Mostly Sunny | 5 to 10 mph NW | 1% |
| Thursday Night | 40°F | Partly Cloudy | 5 mph N | 0% |
| Friday | 56°F | Partly Sunny | 0 to 5 mph N | 0% |
| Friday Night | 35°F | Mostly Cloudy | 0 mph | 0% |
| Saturday | 59°F | Mostly Sunny | 0 mph | 0% |
| Saturday Night | 37°F | Mostly Clear | 0 mph | 0% |
| Sunday | 64°F | Sunny | 0 to 5 mph W | 0% |
| Sunday Night | 40°F | Clear | 0 mph | 0% |
| Monday | 70°F | Sunny | 0 to 10 mph SW | 0% |
| Monday Night | 43°F | Clear | 0 to 5 mph W | 0% |
| Tuesday | 70°F | Sunny | 0 to 5 mph NE | 0% |
Forecast source: National Weather Service (api.weather.gov) for St. Marys (39.194, -96.064). Updated through the day.
Growing snapshot for St. Marys
Last spring frost
Apr 18
First fall frost
Oct 19
Growing season
183 days
Hardiness zone
6b
More local growing data for St. Marys: nearby ZIP 66536 weather · frost dates · planting calendar · Kansas frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Wamego 4 W, Ks (16.1 mi from St. Marys). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.