Frost dates for Rauville 2 W, SD
At Rauville 2 W, the median last spring frost (32°F) is May 7 and the median first fall frost is Sep 28, for a typical growing season of 143 days. For a 90% chance that the last frost has passed, wait until May 20. Nearby ZIP codes are in USDA hardiness zone 4b.
- May 7Last spring frost (median)50% chance of 32°F after this date
- May 20Safer planting date10% chance of 32°F after this date
- Sep 28First fall frost (median)50% chance of 32°F by this date
- 143 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | May 4 | May 15 | May 29 |
| 32°F | Apr 24 | May 7 | May 20 |
| 28°F | Apr 13 | Apr 28 | May 11 |
| 24°F | Apr 5 | Apr 18 | May 2 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 7 | Sep 19 | Oct 2 |
| 32°F | Sep 16 | Sep 28 | Oct 13 |
| 28°F | Sep 24 | Oct 8 | Oct 23 |
| 24°F | Oct 5 | Oct 22 | Nov 4 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 107 days | 125 days | 141 days |
| 32°F | 126 days | 143 days | 160 days |
| 28°F | 144 days | 163 days | 183 days |
| 24°F | 164 days | 184 days | 205 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 57235 | 4b | -25 to -20°F | 17 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00396969, at 44.9733, -97.1494, elevation 529 m (1,737 ft).
- Data quality: Estimated from nearby stations (2+ years), 10 years of freeze data.
- Average days per year at or below 32°F: 183.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Watertown Regional Airport (8 km)
- Watertown 2 S (12 km)
- Castlewood #2 (29 km)
- Castlewood (29 km)
- Summit 1 W (37 km)
- Clear Lake (44 km)
- Clark (47 km)
- Clark No2 (47 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.