Ballwin, MO Weather & Growing Conditions
Tonight
73°F
Slight Chance Showers And Thunderstorms then Mostly Clear
A slight chance of showers and thunderstorms before 9pm. Mostly clear, with a low around 73. Heat index values as high as 102. Southeast wind around 2 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 73°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 2 mph SE | 23% |
| Saturday | 97°F | Mostly Sunny | 2 to 6 mph SW | 5% |
| Saturday Night | 74°F | Partly Cloudy | 3 mph SW | 2% |
| Sunday | 93°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 5 mph W | 19% |
| Sunday Night | 68°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 5 mph N | 62% |
| Monday | 79°F | Showers And Thunderstorms Likely | 3 to 7 mph N | 71% |
| Monday Night | 60°F | Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms | 3 to 7 mph N | 71% |
| Tuesday | 71°F | Slight Chance Rain Showers then Mostly Cloudy | 8 mph N | 21% |
| Tuesday Night | 55°F | Mostly Cloudy | 3 to 7 mph N | 6% |
| Wednesday | 74°F | Mostly Sunny | 6 mph N | 1% |
| Wednesday Night | 56°F | Partly Cloudy | 1 to 5 mph N | 1% |
| Thursday | 75°F | Mostly Sunny | 5 mph N | 3% |
| Thursday Night | 58°F | Partly Cloudy | 3 mph NE | 3% |
| Friday | 75°F | Mostly Sunny | 5 mph NE | 8% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Ballwin, MO
Last spring frost
Apr 4
First fall frost
Oct 29
Growing season
206 days
Hardiness zone
7a
Explore more for Ballwin, MO: full frost dates · planting calendar · Missouri frost dates
Climate data from the nearest NOAA station, St Charles 7 Ssw, Mo (8.1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.