USDA Hardiness Zone 7b
Frost Dates for 37317 — Copperhill, Tennessee
NOAA 1991–2020 normals from Murphy 4ESE, NC (1,600 ft), 24 miles east.
Updated
In Copperhill, the last spring frost (32°F) is around April 22 in half of years and has passed by May 7 in nine years out of ten. The first fall frost comes around October 20, as early as October 8 one year in ten, leaving a typical freeze-free season of 180 days (NOAA, Murphy 4ESE, NC).
- Last spring frost
- April 22
- First fall frost
- October 20
- Growing season
- 180 days
- Hardiness zone
- 7b
50% probability
50% probability
freeze-free, 50%
5 to 10°F (-15.0 to -12.2°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 40%
- Snow per year
- 1.1"
median, 1991–2020
median, 1991–2020
12 of 30 observed
NOAA normal
Frost risk by date in Copperhill
Half of springs at Murphy 4ESE, NC see their last 32°F night by April 22; only one in ten is past it by April 7, and one in ten still has one after May 7. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 2 20%, and after May 7 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 78% of the 144 Tennessee stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 20 in half of years, as early as October 8 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 10 days later, around October 30; in spring the one-in-ten date for 28°F is April 27, 10 days before the 32°F one. The freeze-free season lasts 180 days in a typical year, shorter than at 95% of the 144 Tennessee stations; it reaches 200 days one year in ten and falls short of 160 one year in ten. On average 103 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 12 days longer, to about May 4, and return around October 13. Severe cold of 16°F or below comes every winter, usually between December 8 and February 24.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 19 | Apr 24 | Apr 29 | May 1 | May 4 | May 6 | May 9 | May 13 | May 18 |
| 32°F | Apr 7 | Apr 12 | Apr 15 | Apr 19 | Apr 22 | Apr 25 | Apr 30 | May 2 | May 7 |
| 28°F | Mar 21 | Mar 29 | Apr 2 | Apr 6 | Apr 9 | Apr 13 | Apr 17 | Apr 22 | Apr 27 |
| 24°F | Mar 4 | Mar 12 | Mar 19 | Mar 24 | Mar 28 | Mar 31 | Apr 3 | Apr 7 | Apr 14 |
| 20°F | Feb 14 | Feb 24 | Feb 28 | Mar 5 | Mar 11 | Mar 16 | Mar 22 | Mar 27 | Apr 1 |
| 16°F | Jan 28 | Feb 4 | Feb 11 | Feb 17 | Feb 24 | Feb 28 | Mar 6 | Mar 13 | Mar 21 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 5 | Oct 8 | Oct 10 | Oct 13 | Oct 15 | Oct 18 | Oct 21 | Oct 26 |
| 32°F | Oct 8 | Oct 12 | Oct 15 | Oct 18 | Oct 20 | Oct 23 | Oct 26 | Oct 29 | Nov 2 |
| 28°F | Oct 16 | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 8 | Nov 14 |
| 24°F | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 13 | Nov 17 | Nov 21 | Nov 29 |
| 20°F | Nov 7 | Nov 12 | Nov 16 | Nov 21 | Nov 25 | Nov 29 | Dec 2 | Dec 7 | Dec 17 |
| 16°F | Nov 18 | Nov 24 | Dec 1 | Dec 4 | Dec 8 | Dec 15 | Dec 22 | Dec 30 | Jan 8 |
Freeze probabilities 1991–2020 at Murphy 4ESE, NC, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 37317 →Compare Copperhill with another place →
Weather by month in Copperhill
July is the warmest month at Murphy 4ESE, NC, averaging 87°F by day and 63°F at night; January is the coldest at 50°F and 25°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 26% of years.
Warmth for growing adds up to 3,839 growing degree days a year (base 50°F), fewer than at 86% of the 144 Tennessee stations. 37% of them (1,412) have built up by the end of June, and July adds the most, 772. Precipitation totals 59.5 inches a year, most in December (6.0") and least in October (3.5"); May to September bring 41% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 50 | 25 | 5.1 | 100% | 22 | 15 |
| Feb | 54 | 28 | 5.3 | 100% | 19 | 19 |
| Mar | 62 | 34 | 5.3 | 100% | 15 | 80 |
| Apr | 71 | 41 | 5.2 | 96% | 5 | 218 |
| May | 78 | 51 | 4.8 | 26% | <1 | 440 |
| Jun | 84 | 59 | 5.4 | 0% | 0 | 640 |
| Jul | 87 | 63 | 5.3 | 0% | 0 | 772 |
| Aug | 86 | 62 | 4.7 | 0% | 0 | 749 |
| Sep | 81 | 56 | 4.3 | 1% | 0 | 557 |
| Oct | 72 | 43 | 3.5 | 85% | 5 | 261 |
| Nov | 61 | 33 | 4.6 | 100% | 16 | 66 |
| Dec | 53 | 28 | 6.0 | 100% | 21 | 24 |
Monthly normals 1991–2020 at Murphy 4ESE, NC (1,600 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Tellico Plains, TN, 25 miles north of Copperhill and 690 feet lower, has a last frost 9 days earlier (April 13), a first frost 4 days later (October 24), a season 13 days longer.
When it snows in Copperhill, Tennessee
Measurable snow is rare here: only 12 of 30 winters from 1991 to 2020 recorded 0.1 inch or more at Cleveland Fltr Plt, TN, 27.2 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 37317
| When | What to do |
|---|---|
| February 11 – February 25 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 25 – March 11 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 25 – April 8 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 22 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 28 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 6 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 20 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 37317 is 24 miles from Murphy 4ESE, NC, which stands at 1,600 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 28906 (Murphy). The 2023 USDA Plant Hardiness Zone Map lists ZIP 37317 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Tennessee →
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.