Frost dates for Rock Island State Park, TN
At Rock Island State Park, the median last spring frost (32°F) is Apr 6 and the median first fall frost is Oct 30, for a typical growing season of 207 days. For a 90% chance that the last frost has passed, wait until Apr 22. Nearby ZIP codes are in USDA hardiness zone 7b.
- Apr 6Last spring frost (median)50% chance of 32°F after this date
- Apr 22Safer planting date10% chance of 32°F after this date
- Oct 30First fall frost (median)50% chance of 32°F by this date
- 207 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 | Apr 4 | Apr 18 | May 3 |
| 32°F | Mar 22 | Apr 6 | Apr 22 |
| 28°F | Mar 8 | Mar 26 | Apr 9 |
| 24°F | Feb 20 | Mar 13 | Mar 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 |
|---|---|---|---|
| 36°F | Oct 10 | Oct 21 | Nov 4 |
| 32°F | Oct 17 | Oct 30 | Nov 14 |
| 28°F | Oct 26 | Nov 9 | Nov 28 |
| 24°F | Nov 5 | Nov 23 | Dec 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 | 166 days | 185 days | 206 days |
| 32°F | 187 days | 207 days | 230 days |
| 28°F | 206 days | 230 days | 254 days |
| 24°F | 232 days | 257 days | 285 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 |
|---|---|---|---|
| 38550 | 7b | 5 to 10°F | 4 km |
| 38587 | 7b | 5 to 10°F | 7 km |
| 38581 | 7b | 5 to 10°F | 8 km |
| 38579 | 7b | 5 to 10°F | 9 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 USC00407808, at 35.8092, -85.6417, elevation 268 m (880 ft).
- Data quality: Representative (10+ years), 14 years of freeze data.
- Average days per year at or below 32°F: 74.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Sparta Wastewater Plant (19 km)
- Mc Minnville (20 km)
- Smithville 2 SE (20 km)
- Fall Creek Falls State Park (32 km)
- Lancaster Edgar Evins Marina (35 km)
- Cookeville (35 km)
- Woodbury 1 WNW (40 km)
- Pikeville (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.