St. Charles, IA Weather & Growing Conditions
This Afternoon
86°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms. Partly sunny. High near 86, with temperatures falling to around 81 in the afternoon. West wind around 7 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 86°F | Slight Chance Showers And Thunderstorms | 7 mph W | 20% |
| Tonight | 62°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 6 to 9 mph N | 73% |
| Sunday | 65°F | Chance Rain Showers then Chance Drizzle | 8 to 12 mph NNE | 45% |
| Sunday Night | 57°F | Rain Showers Likely | 12 mph NE | 73% |
| Monday | 59°F | Rain Showers | 10 mph NE | 81% |
| Monday Night | 53°F | Rain Showers Likely | 7 to 10 mph NNE | 67% |
| Tuesday | 59°F | Mostly Cloudy | 8 mph NE | 13% |
| Tuesday Night | 48°F | Partly Cloudy | 2 to 7 mph NE | 2% |
| Wednesday | 63°F | Mostly Sunny | 5 mph ENE | 0% |
| Wednesday Night | 52°F | Partly Cloudy | 3 mph E | 6% |
| Thursday | 66°F | Slight Chance Rain Showers | 5 mph SE | 23% |
| Thursday Night | 57°F | Slight Chance Rain Showers | 3 mph ESE | 24% |
| Friday | 68°F | Slight Chance Rain Showers | 2 to 6 mph ESE | 24% |
| Friday Night | 59°F | Mostly Cloudy | 5 mph E | 11% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Charles, IA
Last spring frost
Apr 24
First fall frost
Oct 12
Growing season
168 days
Hardiness zone
5b
Explore more for St. Charles, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Indianola 2W, Ia (8.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.