Frost dates for Erwin 1 W, TN
At Erwin 1 W, the median last spring frost (32°F) is Apr 21 and the median first fall frost is Oct 23, for a typical growing season of 183 days. For a 90% chance that the last frost has passed, wait until May 11. Nearby ZIP codes are in USDA hardiness zones 7a to 7b.
- Apr 21Last spring frost (median)50% chance of 32°F after this date
- May 11Safer planting date10% chance of 32°F after this date
- Oct 23First fall frost (median)50% chance of 32°F by this date
- 183 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 18 | May 3 | May 20 |
| 32°F | Apr 4 | Apr 21 | May 11 |
| 28°F | Mar 20 | Apr 7 | Apr 30 |
| 24°F | Mar 6 | Mar 26 | Apr 12 |
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 3 | Oct 14 | Oct 27 |
| 32°F | Oct 11 | Oct 23 | Nov 4 |
| 28°F | Oct 18 | Nov 1 | Nov 13 |
| 24°F | Oct 28 | Nov 9 | Nov 27 |
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 | 141 days | 163 days | 182 days |
| 32°F | 160 days | 183 days | 203 days |
| 28°F | 180 days | 205 days | 229 days |
| 24°F | 206 days | 229 days | 254 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 |
|---|---|---|---|
| 37650 | 7a | 0 to 5°F | 7 km |
| 37692 | 7a | 0 to 5°F | 12 km |
| 37659 | 7a | 0 to 5°F | 17 km |
| 37690 | 7b | 5 to 10°F | 17 km |
| 37657 | 7a | 0 to 5°F | 18 km |
| 37681 | 7b | 5 to 10°F | 22 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 USC00402934, at 36.1422, -82.4261, elevation 524 m (1,720 ft).
- Data quality: Standard (24+ years of data), 26 years of freeze data.
- Average days per year at or below 32°F: 98.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Elizabethton (28 km)
- Roan Mountain 3sw (30 km)
- Bristol Tri City Airport (37 km)
- Greeneville Exp. Station (38 km)
- Kingsport (43 km)
- Rogersville 1 NE (59 km)
- Mountain City 2 (67 km)
- Newport 1 NW (72 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.