Frost dates for Torrington Exp. Farm, WY
At Torrington Exp. Farm, the median last spring frost (32°F) is May 14 and the median first fall frost is Sep 24, for a typical growing season of 130 days. For a 90% chance that the last frost has passed, wait until May 28. Nearby ZIP codes are in USDA hardiness zone 5a.
- May 14Last spring frost (median)50% chance of 32°F after this date
- May 28Safer planting date10% chance of 32°F after this date
- Sep 24First fall frost (median)50% chance of 32°F by this date
- 130 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 13 | May 26 | Jun 10 |
| 32°F | May 2 | May 14 | May 28 |
| 28°F | Apr 21 | May 3 | May 17 |
| 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 2 | Sep 15 | Sep 25 |
| 32°F | Sep 10 | Sep 24 | Oct 5 |
| 28°F | Sep 20 | Oct 3 | Oct 17 |
| 24°F | Sep 29 | Oct 13 | Oct 26 |
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 | 94 days | 111 days | 129 days |
| 32°F | 111 days | 130 days | 148 days |
| 28°F | 131 days | 152 days | 170 days |
| 24°F | 151 days | 171 days | 189 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 82240 | 5a | -20 to -15°F | 12 km |
| 82223 | 5a | -20 to -15°F | 15 km |
| 82218 | 5a | -20 to -15°F | 17 km |
| 82243 | 5a | -20 to -15°F | 18 km |
| 69358 | 5a | -20 to -15°F | 20 km |
| 82244 | 5a | -20 to -15°F | 27 km |
| 82212 | 5a | -20 to -15°F | 33 km |
| 82217 | 5a | -20 to -15°F | 36 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 USC00488995, at 42.0803, -104.2236, elevation 1249 m (4,098 ft).
- Data quality: Representative (10+ years), 14 years of freeze data.
- Average days per year at or below 32°F: 190.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Torrington Muni Airport (6 km)
- Lingle 2wsw (15 km)
- Yoder 5 W (23 km)
- Old Fort Laramie (31 km)
- Whalen Dam Usbr (38 km)
- Torrington 29n (46 km)
- La Grange (49 km)
- Guernsey 2nw (50 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.