Frost dates for Ridgway, CO
At Ridgway, the median last spring frost (32°F) is Jun 11 and the median first fall frost is Sep 13, for a typical growing season of 92 days. For a 90% chance that the last frost has passed, wait until Jun 30. Nearby ZIP codes are in USDA hardiness zone 6a.
- Jun 11Last spring frost (median)50% chance of 32°F after this date
- Jun 30Safer planting date10% chance of 32°F after this date
- Sep 13First fall frost (median)50% chance of 32°F by this date
- 92 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 27 | Jun 11 | Jun 30 |
| 28°F | May 5 | May 26 | Jun 14 |
| 24°F | Apr 24 | May 8 | May 31 |
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 | Sep 1 | Sep 13 | Sep 25 |
| 28°F | Sep 10 | Sep 23 | Oct 4 |
| 24°F | Sep 19 | Oct 2 | Oct 14 |
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 | 39 days | 64 days | 85 days |
| 32°F | 71 days | 92 days | 112 days |
| 28°F | 94 days | 117 days | 138 days |
| 24°F | 122 days | 144 days | 165 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 |
|---|---|---|---|
| 81432 | 6a | -10 to -5°F | 3 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 USC00057020, at 38.1500, -107.7583, elevation 2148 m (7,049 ft).
- Data quality: Representative (10+ years), 19 years of freeze data.
- Average days per year at or below 32°F: 223.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Ouray #2 (16 km)
- Ouray (16 km)
- Telluride 4wnw (25 km)
- Placerville (30 km)
- Cimarron (37 km)
- Montrose #2 (39 km)
- Silverton (39 km)
- Lake City 1nne (41 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.