Frost dates for Bristol Tri City Airport, TN
At Bristol Tri City Airport, the median last spring frost (32°F) is Apr 16 and the median first fall frost is Oct 24, for a typical growing season of 190 days. For a 90% chance that the last frost has passed, wait until May 5. Nearby ZIP codes are in USDA hardiness zone 7b.
- Apr 16Last spring frost (median)50% chance of 32°F after this date
- May 5Safer planting date10% chance of 32°F after this date
- Oct 24First fall frost (median)50% chance of 32°F by this date
- 190 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 14 | Apr 29 | May 17 |
| 32°F | Mar 30 | Apr 16 | May 5 |
| 28°F | Mar 16 | Apr 1 | Apr 18 |
| 24°F | Feb 28 | Mar 21 | Apr 5 |
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 4 | Oct 15 | Oct 28 |
| 32°F | Oct 11 | Oct 24 | Nov 4 |
| 28°F | Oct 19 | Nov 1 | Nov 15 |
| 24°F | Oct 30 | Nov 12 | Nov 29 |
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 | 147 days | 169 days | 188 days |
| 32°F | 166 days | 190 days | 210 days |
| 28°F | 192 days | 212 days | 235 days |
| 24°F | 213 days | 237 days | 263 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 |
|---|---|---|---|
| 37686 | 7b | 5 to 10°F | 6 km |
| 37617 | 7b | 5 to 10°F | 7 km |
| 37615 | 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 USW00013877, at 36.4731, -82.4044, elevation 457 m (1,500 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 94.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Kingsport (12 km)
- Elizabethton (19 km)
- Erwin 1 W (37 km)
- Roan Mountain 3sw (44 km)
- Rogersville 1 NE (52 km)
- Mountain City 2 (54 km)
- Greeneville Exp. Station (57 km)
- Morristown Radio Wcrk (88 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.