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Westport, SD Weather & Growing Conditions

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

This Afternoon
64°F
Areas Of Drizzle
Areas of drizzle and patchy fog. Cloudy, with a high near 64. East wind around 14 mph, with gusts as high as 24 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Westport

WhenTempForecastWindPrecip
This Afternoon 64°F Areas Of Drizzle 14 mph E 53%
Tonight 54°F Areas Of Drizzle 8 to 12 mph NE 26%
Saturday 67°F Areas Of Fog 9 to 13 mph NE 2%
Saturday Night 52°F Cloudy 10 mph NE 9%
Sunday 66°F Cloudy then Slight Chance Rain Showers 13 mph NE 16%
Sunday Night 49°F Chance Rain Showers 5 to 9 mph ENE 36%
Monday 65°F Chance Rain Showers then Mostly Cloudy 8 mph E 35%
Monday Night 46°F Mostly Cloudy 7 mph ESE 2%
Tuesday 67°F Partly Sunny 5 to 13 mph SE 2%
Tuesday Night 49°F Mostly Cloudy 10 mph SSE 13%
Wednesday 70°F Partly Sunny then Slight Chance Rain Showers 12 to 16 mph SSE 16%
Wednesday Night 52°F Chance Rain Showers 8 to 13 mph SSE 26%
Thursday 72°F Chance Rain Showers then Partly Sunny 9 mph SSE 26%
Thursday Night 53°F Partly Cloudy 7 mph SSE 11%

Forecast source: National Weather Service (api.weather.gov) for Westport (45.648, -98.498). Updated through the day.

Growing snapshot for Westport

Last spring frost
May 7
First fall frost
Sep 29
Growing season
145 days
Hardiness zone
4a

More local growing data for Westport: nearby ZIP 57426 weather · frost dates · planting calendar · South Dakota frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, Columbia 8 N, Sd (9.2 mi from Westport). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.