Frost dates for Highmore 1 W, SD
At Highmore 1 W, the median last spring frost (32°F) is May 12 and the median first fall frost is Oct 1, for a typical growing season of 142 days. For a 90% chance that the last frost has passed, wait until May 28. Nearby ZIP codes are in USDA hardiness zone 4b.
- May 12Last spring frost (median)50% chance of 32°F after this date
- May 28Safer planting date10% chance of 32°F after this date
- Oct 1First fall frost (median)50% chance of 32°F by this date
- 142 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 7 | May 21 | Jun 5 |
| 32°F | Apr 28 | May 12 | May 28 |
| 28°F | Apr 14 | May 2 | May 17 |
| 24°F | Apr 7 | Apr 24 | May 10 |
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 10 | Sep 22 | Oct 5 |
| 32°F | Sep 17 | Oct 1 | Oct 14 |
| 28°F | Sep 25 | Oct 10 | Oct 25 |
| 24°F | Oct 3 | Oct 19 | Nov 3 |
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 | 103 days | 124 days | 143 days |
| 32°F | 120 days | 142 days | 160 days |
| 28°F | 136 days | 158 days | 179 days |
| 24°F | 154 days | 176 days | 199 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 |
|---|---|---|---|
| 57345 | 4b | -25 to -20°F | 6 km |
| 57540 | 4b | -25 to -20°F | 14 km |
| 57371 | 4b | -25 to -20°F | 21 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 USC00393832, at 44.5222, -99.4550, elevation 576 m (1,888 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 170.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Stephan 2 NW (28 km)
- Harrold 12 SSW (33 km)
- Highmore 23 N (36 km)
- Miller (38 km)
- Lake Sharpe Prj (51 km)
- Onida 4 NW (59 km)
- Gann Valley 4nw (60 km)
- Gann Valley 3 NNE (62 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.