St. Charles, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. Charles, a city in Madison County, Iowa.
Overnight
67°F
Mostly Cloudy
Mostly cloudy, with a low around 67. South wind around 6 mph.
7-day forecast for St. Charles
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 67°F | Mostly Cloudy | 6 mph S | 4% |
| Tuesday | 85°F | Chance Showers And Thunderstorms | 6 to 9 mph W | 41% |
| Tuesday Night | 64°F | Showers And Thunderstorms | 7 to 12 mph NNE | 88% |
| Wednesday | 72°F | Showers And Thunderstorms Likely | 8 mph NNE | 68% |
| Wednesday Night | 58°F | Chance Showers And Thunderstorms | 2 to 7 mph NE | 41% |
| Thursday | 80°F | Mostly Sunny | 5 mph ENE | 8% |
| Thursday Night | 62°F | Mostly Clear | 5 mph SE | 5% |
| Friday | 85°F | Mostly Sunny | 3 to 7 mph S | 5% |
| Friday Night | 67°F | Mostly Clear | 6 mph S | 10% |
| Saturday | 89°F | Sunny | 5 to 10 mph SSW | 5% |
| Saturday Night | 73°F | Mostly Clear | 9 to 15 mph SSW | 10% |
| Sunday | 90°F | Mostly Sunny | 14 mph SSW | 10% |
| Sunday Night | 72°F | Slight Chance Showers And Thunderstorms | 13 mph S | 24% |
| Monday | 91°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 12 to 15 mph SSW | 24% |
Forecast source: National Weather Service (api.weather.gov) for St. Charles (41.287, -93.807). Updated through the day.
Growing snapshot for St. Charles
Last spring frost
Apr 24
First fall frost
Oct 12
Growing season
168 days
Hardiness zone
5b
More local growing data for St. Charles: nearby ZIP 50240 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Indianola 2W, Ia (8.9 mi from St. Charles). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.