Frost dates for Hot Springs, SD
At Hot Springs, the median last spring frost (32°F) is May 16 and the median first fall frost is Sep 27, for a typical growing season of 133 days. For a 90% chance that the last frost has passed, wait until May 31. Nearby ZIP codes are in USDA hardiness zone 5a.
- May 16Last spring frost (median)50% chance of 32°F after this date
- May 31Safer planting date10% chance of 32°F after this date
- Sep 27First fall frost (median)50% chance of 32°F by this date
- 133 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 16 | May 29 | Jun 12 |
| 32°F | May 4 | May 16 | May 31 |
| 28°F | Apr 24 | May 5 | May 18 |
| 24°F | Apr 10 | Apr 25 | May 7 |
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 3 | Sep 19 | Sep 30 |
| 32°F | Sep 12 | Sep 27 | Oct 9 |
| 28°F | Sep 23 | Oct 7 | Oct 20 |
| 24°F | Oct 2 | Oct 18 | Oct 30 |
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 | 92 days | 112 days | 131 days |
| 32°F | 113 days | 133 days | 150 days |
| 28°F | 135 days | 152 days | 171 days |
| 24°F | 154 days | 174 days | 193 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 |
|---|---|---|---|
| 57747 | 5a | -20 to -15°F | 8 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 USC00394007, at 43.4378, -103.4739, elevation 1085 m (3,560 ft).
- Data quality: Standard (24+ years of data), 29 years of freeze data.
- Average days per year at or below 32°F: 176.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Wind Cave (13 km)
- Oral (17 km)
- Edgemont (31 km)
- Oelrichs (34 km)
- Custer Co Airport (35 km)
- Custer (39 km)
- Edgemont 23 NNW (41 km)
- Ardmore 1 NW (48 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.