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Sinai, SD Weather & Growing Conditions

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

Overnight
57°F
Areas Of Fog
Areas of fog. Cloudy, with a low around 57. Northeast wind 5 to 10 mph.

7-day forecast for Sinai

WhenTempForecastWindPrecip
Overnight 57°F Areas Of Fog 5 to 10 mph NE 10%
Saturday 64°F Patchy Fog 10 to 15 mph NNE 15%
Saturday Night 51°F Mostly Cloudy 10 to 15 mph NNE 7%
Sunday 64°F Mostly Cloudy 15 mph NE 4%
Sunday Night 48°F Chance Rain Showers 10 to 15 mph ENE 47%
Monday 61°F Chance Rain Showers 10 mph E 47%
Monday Night 43°F Mostly Cloudy 5 to 10 mph E 9%
Tuesday 63°F Mostly Sunny 5 to 15 mph SE 3%
Tuesday Night 44°F Partly Cloudy 10 mph SE 2%
Wednesday 66°F Mostly Sunny 10 to 15 mph SSE 7%
Wednesday Night 49°F Chance Rain Showers 10 mph SSE 32%
Thursday 68°F Chance Rain Showers 10 to 15 mph SSE 32%
Thursday Night 52°F Mostly Cloudy then Slight Chance Rain Showers 5 to 10 mph SSE 18%
Friday 70°F Slight Chance Rain Showers then Partly Sunny 10 to 15 mph SSE 18%

Forecast source: National Weather Service (api.weather.gov) for Sinai (44.244, -97.044). Updated through the day.

Growing snapshot for Sinai

Last spring frost
May 3
First fall frost
Oct 2
Growing season
151 days
Hardiness zone
4b

More local growing data for Sinai: nearby ZIP 57061 weather · frost dates · planting calendar · South Dakota frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, Arlington 1 W, Sd (10.3 mi from Sinai). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.