Sinai, SD Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Sinai, a town in Brookings County, South Dakota.
Today
69°F
Partly Sunny
Partly sunny, with a high near 69. Northwest wind around 10 mph.
7-day forecast for Sinai
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 69°F | Partly Sunny | 10 mph NW | 10% |
| Tonight | 52°F | Partly Cloudy | 0 to 5 mph WSW | 4% |
| Wednesday | 76°F | Sunny | 5 to 10 mph SSW | 0% |
| Wednesday Night | 57°F | Mostly Clear | 5 to 10 mph SSW | 0% |
| Thursday | 81°F | Sunny | 10 to 15 mph SSW | 3% |
| Thursday Night | 62°F | Mostly Clear | 10 to 15 mph SSW | 4% |
| Friday | 84°F | Sunny | 10 to 15 mph SSW | 9% |
| Friday Night | 62°F | Mostly Clear | 5 to 10 mph S | 10% |
| Saturday | 86°F | Sunny | 5 to 15 mph SSE | 7% |
| Saturday Night | 65°F | Slight Chance Showers And Thunderstorms | 10 to 15 mph ESE | 22% |
| Sunday | 83°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 15 mph E | 15% |
| Sunday Night | 64°F | Slight Chance Showers And Thunderstorms | 10 to 15 mph E | 26% |
| Monday | 82°F | Chance Showers And Thunderstorms then Partly Sunny | 10 to 15 mph ENE | 26% |
| Monday Night | 63°F | Slight Chance Showers And Thunderstorms | 10 to 15 mph ENE | 15% |
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 Aug 4, 2026.