St. Mary, KY Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. Mary, a city in Marion County, Kentucky.
This Afternoon
94°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms after 5pm. Sunny, with a high near 94. Heat index values as high as 101. Northwest wind around 5 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for St. Mary
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 94°F | Slight Chance Showers And Thunderstorms | 5 mph NW | 16% |
| Tonight | 69°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 3 mph NE | 20% |
| Saturday | 93°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 2 mph S | 21% |
| Saturday Night | 70°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 3 mph S | 18% |
| Sunday | 94°F | Mostly Sunny | 3 to 7 mph SW | 7% |
| Sunday Night | 70°F | Partly Cloudy | 5 mph SE | 5% |
| Monday | 89°F | Mostly Sunny then Chance Showers And Thunderstorms | 6 mph NE | 35% |
| Monday Night | 65°F | Chance Showers And Thunderstorms | 6 mph NE | 48% |
| Tuesday | 81°F | Chance Rain Showers then Chance Showers And Thunderstorms | 6 mph NE | 48% |
| Tuesday Night | 61°F | Chance Showers And Thunderstorms | 3 to 7 mph N | 48% |
| Wednesday | 77°F | Chance Rain Showers | 6 mph N | 36% |
| Wednesday Night | 58°F | Slight Chance Rain Showers then Partly Cloudy | 2 to 6 mph N | 22% |
| Thursday | 76°F | Mostly Sunny | 2 to 6 mph N | 9% |
| Thursday Night | 58°F | Partly Cloudy | 2 to 6 mph N | 9% |
Forecast source: National Weather Service (api.weather.gov) for St. Mary (37.583, -85.341). Updated through the day.
Growing snapshot for St. Mary
Last spring frost
Apr 22
First fall frost
Oct 20
Growing season
180 days
Hardiness zone
7a
More local growing data for St. Mary: nearby ZIP 40063 weather · frost dates · planting calendar · Kentucky frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Bradfordsville, Ky (11.8 mi from St. Mary). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.