Frost dates for Lemmon, SD
At Lemmon, the median last spring frost (32°F) is May 10 and the median first fall frost is Sep 30, for a typical growing season of 142 days. For a 90% chance that the last frost has passed, wait until May 24. Nearby ZIP codes are in USDA hardiness zone 4b.
- May 10Last spring frost (median)50% chance of 32°F after this date
- May 24Safer planting date10% chance of 32°F after this date
- Sep 30First 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 8 | May 20 | Jun 2 |
| 32°F | Apr 30 | May 10 | May 24 |
| 28°F | Apr 17 | May 1 | May 14 |
| 24°F | Apr 6 | Apr 20 | May 3 |
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 9 | Sep 22 | Oct 3 |
| 32°F | Sep 18 | Sep 30 | Oct 12 |
| 28°F | Sep 25 | Oct 9 | Oct 22 |
| 24°F | Oct 2 | Oct 18 | Nov 1 |
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 | 106 days | 122 days | 141 days |
| 32°F | 125 days | 142 days | 159 days |
| 28°F | 142 days | 160 days | 178 days |
| 24°F | 161 days | 180 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 |
|---|---|---|---|
| 57638 | 4b | -25 to -20°F | 10 km |
| 57634 | 4b | -25 to -20°F | 29 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 USC00394864, at 45.9397, -102.1575, elevation 782 m (2,567 ft).
- Data quality: Standard (24+ years of data), 27 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
- Shadehill Rsvr (30 km)
- Bison (52 km)
- Lodgepole 5sw (54 km)
- Glad Valley 2 W (66 km)
- Mc Intosh 6 SE (69 km)
- Ralph 1 N (72 km)
- Ludlow 3 SSE (96 km)
- Buffalo 13 ESE (101 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.