USDA Hardiness Zone 7b
Frost Dates for 37615 — Johnson City, Tennessee
NOAA 1991–2020 normals from Bristol Tri City Airport, TN (1,500 ft), 5 miles northeast.
Updated
In Johnson City, the last spring frost (32°F) is around April 16 in half of years and has passed by May 5 in nine years out of ten. The first fall frost comes around October 24, as early as October 11 one year in ten, leaving a typical freeze-free season of 190 days (NOAA, Bristol Tri City Airport, TN).
- Last spring frost
- April 16
- First fall frost
- October 24
- Growing season
- 190 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
- December 7
- Last snow
- March 7
- Winters with snow
- 93%
- Snow per year
- 9.2"
median, 1991–2020
median, 1991–2020
28 of 30 observed
NOAA normal
Frost risk by date in Johnson City
Half of springs at Bristol Tri City Airport, TN see their last 32°F night by April 16; only one in ten is past it by March 30, and one in ten still has one after May 5. Planting tender crops after April 22 leaves a 30% risk of a frost on them, after April 27 20%, and after May 5 10%. The 19 days between the even-odds date and the one-in-ten date is wider than at 84% of the 144 Tennessee stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 24 in half of years, as early as October 11 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 8 days later, around November 1; in spring the one-in-ten date for 28°F is April 18, 17 days before the 32°F one. The freeze-free season lasts 190 days in a typical year, shorter than at 82% of the 144 Tennessee stations; it reaches 210 days one year in ten and falls short of 166 one year in ten. On average 94 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 13 days longer, to about April 29, and return around October 15. Severe cold of 16°F or below comes every winter, usually between December 12 and February 18.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 14 | Apr 19 | Apr 23 | Apr 26 | Apr 29 | May 3 | May 6 | May 11 | May 17 |
| 32°F | Mar 30 | Apr 5 | Apr 9 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 27 | May 5 |
| 28°F | Mar 16 | Mar 22 | Mar 27 | Mar 30 | Apr 1 | Apr 4 | Apr 8 | Apr 12 | Apr 18 |
| 24°F | Feb 28 | Mar 8 | Mar 13 | Mar 17 | Mar 21 | Mar 24 | Mar 27 | Mar 31 | Apr 5 |
| 20°F | Feb 10 | Feb 19 | Feb 25 | Feb 28 | Mar 5 | Mar 10 | Mar 15 | Mar 19 | Mar 26 |
| 16°F | Jan 22 | Jan 31 | Feb 6 | Feb 12 | Feb 18 | Feb 25 | Mar 1 | Mar 8 | Mar 18 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 4 | Oct 7 | Oct 10 | Oct 13 | Oct 15 | Oct 18 | Oct 20 | Oct 24 | Oct 28 |
| 32°F | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 26 | Oct 29 | Nov 1 | Nov 4 |
| 28°F | Oct 19 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 15 |
| 24°F | Oct 30 | Nov 2 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 23 | Nov 29 |
| 20°F | Nov 9 | Nov 14 | Nov 18 | Nov 23 | Nov 27 | Nov 30 | Dec 3 | Dec 8 | Dec 17 |
| 16°F | Nov 22 | Nov 29 | Dec 4 | Dec 8 | Dec 12 | Dec 17 | Dec 23 | Dec 28 | Jan 5 |
Freeze probabilities 1991–2020 at Bristol Tri City Airport, TN, 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 37615 →Compare Johnson City with another place →
Weather by month in Johnson City
July is the warmest month at Bristol Tri City Airport, TN, averaging 86°F by day and 65°F at night; January is the coldest at 47°F and 26°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 86% of years and May still brings one in 15% of years.
Warmth for growing adds up to 3,903 growing degree days a year (base 50°F), fewer than at 85% of the 144 Tennessee stations. 37% of them (1,460) have built up by the end of June, and July adds the most, 792. Precipitation totals 44.0 inches a year, most in July (5.0") and least in October (2.5"); May to September bring 44% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 47 | 26 | 3.7 | 100% | 22 | 12 |
| Feb | 51 | 29 | 3.8 | 100% | 18 | 19 |
| Mar | 59 | 35 | 4.0 | 100% | 12 | 79 |
| Apr | 69 | 43 | 3.8 | 86% | 4 | 225 |
| May | 77 | 52 | 3.8 | 15% | <1 | 458 |
| Jun | 84 | 61 | 3.9 | 0% | 0 | 667 |
| Jul | 86 | 65 | 5.0 | 0% | 0 | 792 |
| Aug | 86 | 63 | 3.8 | 0% | 0 | 759 |
| Sep | 81 | 56 | 2.8 | 0% | 0 | 557 |
| Oct | 70 | 44 | 2.5 | 79% | 3 | 253 |
| Nov | 59 | 34 | 3.1 | 100% | 15 | 62 |
| Dec | 50 | 29 | 3.8 | 100% | 20 | 19 |
Monthly normals 1991–2020 at Bristol Tri City Airport, TN (1,500 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, Kingsport, TN, 9 miles northwest of Johnson City and 216 feet lower, has a last frost 7 days earlier (April 9), a first frost 5 days later (October 29), a season 13 days longer.
When it snows in Johnson City, Tennessee
The first measurable snow (0.1 inch or more) in Johnson City usually arrives around December 7, and the last of the season around March 7. Those are the middle dates across the winters of 1991–2020 at Bristol Tri City Airport, TN, 5.2 miles away: half of years saw snow earlier, half later. Snow fell in 93% of those winters. The last 32°F night of spring typically comes 40 days after the last snow.
Planting calendar for 37615
| When | What to do |
|---|---|
| February 5 – February 19 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 19 – March 5 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 19 – April 2 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 16 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 1 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 10 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 24 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 37615 is 5 miles from Bristol Tri City Airport, TN, which stands at 1,500 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 37615 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.