Gann Valley, SD Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Gann Valley, a community in Buffalo County, South Dakota.
This Afternoon
70°F
Patchy Fog
Patchy fog. Cloudy, with a high near 70. North wind around 3 mph.
7-day forecast for Gann Valley
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 70°F | Patchy Fog | 3 mph N | 7% |
| Tonight | 57°F | Patchy Fog | 3 to 8 mph N | 6% |
| Saturday | 65°F | Patchy Fog then Cloudy | 9 to 13 mph NNE | 8% |
| Saturday Night | 54°F | Cloudy | 8 to 13 mph NE | 10% |
| Sunday | 62°F | Chance Rain Showers | 14 mph ENE | 47% |
| Sunday Night | 51°F | Rain Showers | 8 to 12 mph ENE | 89% |
| Monday | 60°F | Rain Showers | 10 mph E | 89% |
| Monday Night | 47°F | Mostly Cloudy | 6 to 9 mph ESE | 14% |
| Tuesday | 65°F | Mostly Cloudy | 6 to 15 mph SE | 10% |
| Tuesday Night | 51°F | Mostly Cloudy | 14 mph SE | 11% |
| Wednesday | 69°F | Chance Rain Showers | 14 to 17 mph SSE | 29% |
| Wednesday Night | 54°F | Chance Rain Showers | 10 to 15 mph SSE | 33% |
| Thursday | 71°F | Chance Rain Showers then Partly Sunny | 10 mph SSE | 33% |
| Thursday Night | 55°F | Partly Cloudy | 9 mph SE | 11% |
Forecast source: National Weather Service (api.weather.gov) for Gann Valley (44.034, -98.988). Updated through the day.
Growing snapshot for Gann Valley
Last spring frost
May 6
First fall frost
Oct 1
Growing season
148 days
Hardiness zone
4b
More local growing data for Gann Valley: nearby ZIP 57341 weather · frost dates · planting calendar · South Dakota frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Gann Valley 4Nw, Sd (3.5 mi from Gann Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.