Irondale, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Irondale, a city in Washington County, Missouri.
Today
98°F
Mostly Sunny
Mostly sunny, with a high near 98. Heat index values as high as 100. Southwest wind around 7 mph.
7-day forecast for Irondale
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 98°F | Mostly Sunny | 7 mph SW | 1% |
| Tonight | 71°F | Mostly Clear | 5 mph SW | 3% |
| Sunday | 95°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 5 mph W | 20% |
| Sunday Night | 66°F | Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 1 to 5 mph N | 58% |
| Monday | 82°F | Showers And Thunderstorms Likely | 2 to 6 mph N | 69% |
| Monday Night | 58°F | Showers And Thunderstorms Likely | 3 to 7 mph N | 69% |
| Tuesday | 72°F | Slight Chance Showers And Thunderstorms then Partly Sunny | 3 to 8 mph N | 24% |
| Tuesday Night | 52°F | Partly Cloudy | 2 to 8 mph N | 10% |
| Wednesday | 74°F | Mostly Sunny | 2 to 7 mph N | 2% |
| Wednesday Night | 52°F | Partly Cloudy | 0 to 6 mph N | 1% |
| Thursday | 76°F | Mostly Sunny | 0 to 6 mph N | 3% |
| Thursday Night | 54°F | Partly Cloudy | 0 to 6 mph N | 4% |
| Friday | 77°F | Mostly Sunny | 0 to 6 mph NE | 10% |
| Friday Night | 54°F | Partly Cloudy | 0 to 6 mph NE | 8% |
Forecast source: National Weather Service (api.weather.gov) for Irondale (37.837, -90.670). Updated through the day.
Growing snapshot for Irondale
Last spring frost
Apr 11
First fall frost
Oct 28
Growing season
198 days
Hardiness zone
6b
More local growing data for Irondale: nearby ZIP 63648 weather · frost dates · planting calendar · Missouri frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Potosi 4 Sw, Mo (9.5 mi from Irondale). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.