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Groton, SD Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Groton, a city in Brown County, South Dakota.

This Afternoon
67°F
Cloudy
Cloudy. High near 67, with temperatures falling to around 64 in the afternoon. Northeast wind around 9 mph.

7-day forecast for Groton

WhenTempForecastWindPrecip
This Afternoon 67°F Cloudy 9 mph NE 4%
Tonight 57°F Mostly Cloudy 5 to 9 mph NE 3%
Sunday 64°F Slight Chance Rain Showers then Mostly Cloudy 12 mph NE 16%
Sunday Night 49°F Chance Rain Showers 5 to 9 mph ENE 33%
Monday 65°F Partly Sunny 7 mph E 10%
Monday Night 43°F Partly Cloudy 6 mph ESE 1%
Tuesday 68°F Mostly Sunny 3 to 12 mph SE 0%
Tuesday Night 47°F Partly Cloudy 10 mph SE 2%
Wednesday 69°F Mostly Sunny 10 to 17 mph SSE 9%
Wednesday Night 52°F Showers And Thunderstorms Likely 12 to 15 mph SSE 61%
Thursday 72°F Showers And Thunderstorms Likely 8 to 12 mph SSE 61%
Thursday Night 54°F Mostly Cloudy 7 mph SSE 9%
Friday 75°F Partly Sunny 6 to 12 mph SSE 9%
Friday Night 58°F Mostly Cloudy then Slight Chance Rain Showers 13 mph SSE 21%

Forecast source: National Weather Service (api.weather.gov) for Groton (45.452, -98.100). Updated through the day.

Growing snapshot for Groton

Last spring frost
May 6
First fall frost
Oct 4
Growing season
150 days
Hardiness zone
4a

More local growing data for Groton: nearby ZIP 57445 weather · frost dates · planting calendar · South Dakota frost dates

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Climate data from the nearest NOAA station, Andover #2, Sd (10.7 mi from Groton). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.