Sinai, SD Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Sinai, a town in Brookings County, South Dakota.
This Afternoon
43°F
Rain Showers
Rain showers. Cloudy, with a high near 43. Northwest wind around 20 mph, with gusts as high as 35 mph. Chance of precipitation is 100%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast for Sinai
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 43°F | Rain Showers | 20 mph NW | 100% |
| Tonight | 33°F | Rain Showers Likely then Cloudy | 15 mph NNW | 68% |
| Thursday | 41°F | Mostly Cloudy | 10 to 15 mph N | 0% |
| Thursday Night | 27°F | Mostly Cloudy | 0 to 10 mph NNE | 0% |
| Friday | 42°F | Mostly Sunny | 0 to 5 mph SE | 0% |
| Friday Night | 28°F | Partly Cloudy | 5 mph S | 0% |
| Saturday | 52°F | Mostly Sunny | 5 to 10 mph SW | 0% |
| Saturday Night | 33°F | Mostly Clear | 5 mph W | 0% |
| Sunday | 57°F | Sunny | 5 to 10 mph WSW | 0% |
| Sunday Night | 38°F | Mostly Clear | 5 to 10 mph SSW | 0% |
| Monday | 60°F | Sunny | 10 mph W | 0% |
| Monday Night | 35°F | Mostly Clear | 5 mph NW | 0% |
| Tuesday | 54°F | Mostly Sunny | 5 mph NW | 1% |
| Tuesday Night | 36°F | Partly Cloudy | 5 mph SE | 0% |
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
Aurora
Brookings
Bruce
Bushnell
Elkton
Newdale Colony
Norfeld Colony
Rolland Colony
Spring Lake Colony
Volga
Ward
White
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 Nov 5, 2026.