Frost dates for Worland, WY
At Worland, the median last spring frost (32°F) is May 13 and the median first fall frost is Sep 26, for a typical growing season of 133 days. For a 90% chance that the last frost has passed, wait until May 27. Nearby ZIP codes are in USDA hardiness zones 4b to 5a.
- May 13Last spring frost (median)50% chance of 32°F after this date
- May 27Safer planting date10% chance of 32°F after this date
- Sep 26First 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 15 | May 30 | Jun 13 |
| 32°F | May 2 | May 13 | May 27 |
| 28°F | Apr 19 | May 1 | May 15 |
| 24°F | Apr 7 | Apr 21 | 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 2 | Sep 16 | Sep 28 |
| 32°F | Sep 14 | Sep 26 | Oct 7 |
| 28°F | Sep 23 | Oct 5 | Oct 17 |
| 24°F | Oct 2 | Oct 15 | 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 | 90 days | 108 days | 126 days |
| 32°F | 117 days | 133 days | 151 days |
| 28°F | 137 days | 154 days | 172 days |
| 24°F | 158 days | 175 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% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 82401 | 4b | -25 to -20°F | 18 km |
| 82430 | 4b | -25 to -20°F | 26 km |
| 82432 | 4b | -25 to -20°F | 29 km |
| 82410 | 4b | -25 to -20°F | 46 km |
| 82428 | 5a | -20 to -15°F | 47 km |
| 82442 | 5a | -20 to -15°F | 50 km |
| 82443 | 5a | -20 to -15°F | 50 km |
| 82434 | 4b | -25 to -20°F | 50 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 USW00024062, at 43.9658, -107.9508, elevation 1272 m (4,172 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 182.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Worland (5 km)
- Thermopolis 9ne (28 km)
- Black Mountain (38 km)
- Thermopolis (41 km)
- Basin (47 km)
- Tensleep 4ne (47 km)
- Tensleep 16sse (50 km)
- Greybull (59 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.