Grenville, SD Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Grenville, a town in Day County, South Dakota.
Tonight
37°F
Light Rain
Rain and areas of fog. Cloudy. Low around 37, with temperatures rising to around 40 overnight. North northwest wind around 20 mph, with gusts as high as 31 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast for Grenville
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 37°F | Light Rain | 20 mph NNW | 84% |
| Wednesday | 42°F | Light Rain | 20 mph NNW | 85% |
| Wednesday Night | 33°F | Patchy Fog | 17 mph NNW | 23% |
| Thursday | 39°F | Patchy Fog then Partly Sunny | 10 to 16 mph N | 3% |
| Thursday Night | 30°F | Mostly Cloudy | 2 to 9 mph ENE | 0% |
| Friday | 42°F | Partly Sunny | 2 to 6 mph S | 0% |
| Friday Night | 32°F | Partly Cloudy | 5 to 8 mph SW | 0% |
| Saturday | 52°F | Mostly Sunny | 8 to 13 mph WSW | 5% |
| Saturday Night | 35°F | Partly Cloudy | 7 to 10 mph WNW | 4% |
| Sunday | 53°F | Sunny | 9 mph WSW | 2% |
| Sunday Night | 40°F | Partly Cloudy | 8 to 12 mph SW | 0% |
| Monday | 55°F | Mostly Sunny | 10 to 15 mph WNW | 0% |
| Monday Night | 38°F | Mostly Clear | 9 mph W | 0% |
| Tuesday | 51°F | Mostly Sunny | 8 mph WSW | 0% |
Forecast source: National Weather Service (api.weather.gov) for Grenville (45.467, -97.390). Updated through the day.
Growing snapshot for Grenville
Last spring frost
May 1
First fall frost
Oct 12
Growing season
164 days
Hardiness zone
4b
More local growing data for Grenville: nearby ZIP 57239 weather · frost dates · planting calendar · South Dakota frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Waubay Natl Wild Life, Sd (6 mi from Grenville). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.