Frost dates for Norris, TN
At Norris, the median last spring frost (32°F) is Apr 22 and the median first fall frost is Oct 25, for a typical growing season of 184 days. For a 90% chance that the last frost has passed, wait until May 9. Nearby ZIP codes are in USDA hardiness zones 7a to 7b.
- Apr 22Last spring frost (median)50% chance of 32°F after this date
- May 9Safer planting date10% chance of 32°F after this date
- Oct 25First fall frost (median)50% chance of 32°F by this date
- 184 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 19 | May 2 | May 18 |
| 32°F | Apr 6 | Apr 22 | May 9 |
| 28°F | Mar 20 | Apr 7 | Apr 30 |
| 24°F | Mar 3 | Mar 26 | Apr 16 |
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 16 | Oct 29 |
| 32°F | Oct 11 | Oct 25 | Nov 6 |
| 28°F | Oct 20 | Nov 3 | Nov 18 |
| 24°F | Nov 1 | Nov 15 | Dec 4 |
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 | 146 days | 165 days | 183 days |
| 32°F | 161 days | 184 days | 205 days |
| 28°F | 182 days | 207 days | 230 days |
| 24°F | 207 days | 234 days | 262 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 |
|---|---|---|---|
| 37828 | 7b | 5 to 10°F | 2 km |
| 37705 | 7b | 5 to 10°F | 5 km |
| 37757 | 7b | 5 to 10°F | 7 km |
| 37769 | 7b | 5 to 10°F | 9 km |
| 37754 | 7b | 5 to 10°F | 9 km |
| 37938 | 7b | 5 to 10°F | 15 km |
| 37714 | 7a | 0 to 5°F | 18 km |
| 37807 | 7b | 5 to 10°F | 22 km |
| 37721 | 7b | 5 to 10°F | 24 km |
| 37866 | 7b | 5 to 10°F | 25 km |
| 37779 | 7b | 5 to 10°F | 27 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 USC00406619, at 36.2131, -84.0603, elevation 338 m (1,110 ft).
- Data quality: Standard (24+ years of data), 30 years of freeze data.
- Average days per year at or below 32°F: 101.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Oak Ridge Asos (26 km)
- Oak Ridge Atdd (29 km)
- Knoxville Exp. Station (36 km)
- Newcomb (39 km)
- Knoxville McGhee Tyson Airport (44 km)
- Lenoir City (51 km)
- Sevierville (52 km)
- Tazewell (53 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.