St. Thomas, MO Weather & Growing Conditions
Today
99°F
Mostly Sunny
Mostly sunny, with a high near 99. Heat index values as high as 101. Southwest wind around 8 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 99°F | Mostly Sunny | 8 mph SW | 1% |
| Tonight | 72°F | Partly Cloudy | 3 mph SW | 8% |
| Sunday | 91°F | Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms | 3 mph W | 40% |
| Sunday Night | 68°F | Showers And Thunderstorms | 3 mph N | 80% |
| Monday | 77°F | Showers And Thunderstorms | 3 to 7 mph NE | 80% |
| Monday Night | 59°F | Chance Rain Showers | 7 mph N | 35% |
| Tuesday | 71°F | Partly Sunny | 7 mph N | 13% |
| Tuesday Night | 53°F | Partly Cloudy | 6 mph NE | 3% |
| Wednesday | 74°F | Mostly Sunny | 5 mph NE | 0% |
| Wednesday Night | 54°F | Partly Cloudy | 3 mph NE | 1% |
| Thursday | 77°F | Mostly Sunny | 3 mph NE | 3% |
| Thursday Night | 58°F | Partly Cloudy | 3 mph NE | 7% |
| Friday | 77°F | Slight Chance Rain Showers | 1 to 5 mph NE | 17% |
| Friday Night | 59°F | Mostly Cloudy | 3 mph E | 10% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Thomas, MO
Last spring frost
Apr 8
First fall frost
Oct 31
Growing season
205 days
Hardiness zone
6b
Explore more for St. Thomas, MO: full frost dates · planting calendar · Missouri frost dates
Climate data from the nearest NOAA station, Jefferson City Wtp, Mo (14.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.