Frost dates for Glendo 6ne, WY
At Glendo 6ne, the median last spring frost (32°F) is May 25 and the median first fall frost is Sep 15, for a typical growing season of 112 days. For a 90% chance that the last frost has passed, wait until Jun 11. Nearby ZIP codes are in USDA hardiness zone 5a.
- May 25Last spring frost (median)50% chance of 32°F after this date
- Jun 11Safer planting date10% chance of 32°F after this date
- Sep 15First fall frost (median)50% chance of 32°F by this date
- 112 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 25 | Jun 8 | Jun 23 |
| 32°F | May 13 | May 25 | Jun 11 |
| 28°F | May 2 | May 13 | May 27 |
| 24°F | Apr 19 | May 2 | May 15 |
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 | Aug 28 | Sep 8 | Sep 18 |
| 32°F | Sep 4 | Sep 15 | Sep 27 |
| 28°F | Sep 10 | Sep 24 | Oct 7 |
| 24°F | Sep 19 | Oct 3 | 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 | 72 days | 93 days | 109 days |
| 32°F | 94 days | 112 days | 130 days |
| 28°F | 114 days | 133 days | 150 days |
| 24°F | 133 days | 152 days | 170 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 |
|---|---|---|---|
| 82215 | 5a | -20 to -15°F | 19 km |
| 82224 | 5a | -20 to -15°F | 32 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 USC00483936, at 42.5283, -104.9153, elevation 1444 m (4,739 ft).
- Data quality: Representative (10+ years), 13 years of freeze data.
- Average days per year at or below 32°F: 204.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Glendo Rsvr Usbr (8 km)
- Guernsey Dam #2 (29 km)
- Guernsey 2nw (30 km)
- Whalen Dam Usbr (39 km)
- Lusk 2 SW (43 km)
- Douglas 1 SE (44 km)
- Old Fort Laramie (46 km)
- Wheatland 4 N (47 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.