St. Charles, SD Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. Charles, a community in Gregory County, South Dakota.
Today
69°F
Slight Chance Rain Showers
A slight chance of rain showers before 1pm. Mostly cloudy, with a high near 69. North northwest wind 5 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for St. Charles
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 69°F | Slight Chance Rain Showers | 5 to 15 mph NNW | 23% |
| Tonight | 54°F | Partly Cloudy | 5 mph W | 3% |
| Wednesday | 76°F | Mostly Sunny | 5 to 10 mph SSW | 2% |
| Wednesday Night | 58°F | Mostly Clear | 10 to 15 mph S | 1% |
| Thursday | 85°F | Sunny | 10 to 20 mph S | 7% |
| Thursday Night | 65°F | Mostly Clear | 15 mph S | 7% |
| Friday | 90°F | Sunny | 10 to 15 mph SSW | 5% |
| Friday Night | 66°F | Mostly Clear | 10 mph S | 7% |
| Saturday | 94°F | Sunny | 10 to 25 mph S | 3% |
| Saturday Night | 67°F | Mostly Clear | 10 to 20 mph S | 7% |
| Sunday | 91°F | Mostly Sunny | 10 to 20 mph SE | 3% |
| Sunday Night | 68°F | Slight Chance Showers And Thunderstorms | 15 to 20 mph E | 19% |
| Monday | 90°F | Slight Chance Showers And Thunderstorms then Partly Sunny | 10 to 20 mph ENE | 19% |
| Monday Night | 67°F | Slight Chance Showers And Thunderstorms | 15 to 20 mph ENE | 16% |
Forecast source: National Weather Service (api.weather.gov) for St. Charles (43.088, -99.095). Updated through the day.
Growing snapshot for St. Charles
Last spring frost
May 3
First fall frost
Oct 10
Growing season
159 days
Hardiness zone
5a
More local growing data for St. Charles: nearby ZIP 57571 weather · frost dates · planting calendar · South Dakota frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Bonesteel, Sd (7.5 mi from St. Charles). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.