Frost dates for May 2sse, ID
At May 2sse, the median last spring frost (32°F) is Jun 12 and the median first fall frost is Sep 6, for a typical growing season of 85 days. For a 90% chance that the last frost has passed, wait until Jun 29. Nearby ZIP codes are in USDA hardiness zones 5a to 5b.
- Jun 12Last spring frost (median)50% chance of 32°F after this date
- Jun 29Safer planting date10% chance of 32°F after this date
- Sep 6First fall frost (median)50% chance of 32°F by this date
- 85 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 |
|---|---|---|---|
| 32°F | May 24 | Jun 12 | Jun 29 |
| 28°F | May 7 | May 20 | Jun 11 |
| 24°F | Apr 25 | May 6 | May 19 |
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 |
|---|---|---|---|
| 32°F | Aug 23 | Sep 6 | Sep 20 |
| 28°F | Sep 3 | Sep 19 | Oct 3 |
| 24°F | Sep 16 | Oct 1 | Oct 15 |
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 | 33 days | 54 days | 75 days |
| 32°F | 63 days | 85 days | 109 days |
| 28°F | 95 days | 118 days | 140 days |
| 24°F | 126 days | 148 days | 166 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 |
|---|---|---|---|
| 83253 | 5a | -20 to -15°F | 12 km |
| 83235 | 5b | -15 to -10°F | 14 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 USC00105685, at 44.5664, -113.8953, elevation 1539 m (5,050 ft).
- Data quality: Representative (10+ years), 17 years of freeze data.
- Average days per year at or below 32°F: 220.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Challis Airport (26 km)
- Leadore #2 (44 km)
- Chilly Barton Flat (66 km)
- Salmon-Ksra (67 km)
- Mackay Lost River Ranger Station (75 km)
- Middle Fork Lodge (90 km)
- Stanley (91 km)
- Stanley Ranger Station (93 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.