St. Peters, MO Weather & Growing Conditions
Today
89°F
Sunny
Sunny, with a high near 89. South wind around 3 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 89°F | Sunny | 3 mph S | 0% |
| Tonight | 70°F | Mostly Clear | 5 mph SE | 0% |
| Wednesday | 91°F | Sunny | 5 mph S | 13% |
| Wednesday Night | 72°F | Chance Showers And Thunderstorms | 6 mph S | 69% |
| Thursday | 87°F | Showers And Thunderstorms Likely | 5 mph S | 69% |
| Thursday Night | 71°F | Chance Showers And Thunderstorms | 3 mph SE | 25% |
| Friday | 88°F | Chance Showers And Thunderstorms then Partly Sunny | 3 mph SW | 25% |
| Friday Night | 71°F | Chance Showers And Thunderstorms | 3 mph S | 27% |
| Saturday | 90°F | Chance Showers And Thunderstorms then Mostly Sunny | 3 mph SW | 27% |
| Saturday Night | 73°F | Mostly Clear | 6 mph S | 6% |
| Sunday | 92°F | Sunny | 5 to 8 mph SW | 5% |
| Sunday Night | 75°F | Mostly Clear | 7 mph S | 5% |
| Monday | 94°F | Sunny | 8 mph SW | 5% |
| Monday Night | 76°F | Slight Chance Showers And Thunderstorms | 7 mph SW | 16% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Peters, MO
Last spring frost
Apr 9
First fall frost
Oct 26
Growing season
198 days
Hardiness zone
7a
Explore more for St. Peters, MO: full frost dates · planting calendar · Missouri frost dates
Climate data from the nearest NOAA station, St Peters 2 Se, Mo (3.1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.