USDA Hardiness Zone 7b
Frost Dates for 37811 — Mooresburg, Tennessee
NOAA 1991–2020 normals from Morristown Radio Wcrk, TN (1,344 ft), 12 miles southwest.
Updated
In Mooresburg, the last spring frost (32°F) is around April 10 in half of years and has passed by April 26 in nine years out of ten. The first fall frost comes around October 28, as early as October 16 one year in ten, leaving a typical freeze-free season of 201 days (NOAA, Morristown Radio Wcrk, TN).
- Last spring frost
- April 10
- First fall frost
- October 28
- Growing season
- 201 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 29
- Last snow
- March 1
- Winters with snow
- 100%
- Snow per year
- 8.8"
median, 1991–2020
median, 1991–2020
27 of 27 observed
NOAA normal
Frost risk by date in Mooresburg
Half of springs at Morristown Radio Wcrk, TN see their last 32°F night by April 10; only one in ten is past it by March 25, and one in ten still has one after April 26. Planting tender crops after April 16 leaves a 30% risk of a frost on them, after April 20 20%, and after April 26 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 53% of the 144 Tennessee stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 28 in half of years, as early as October 16 one year in ten, and holds off past November 9 one year in ten. A hard freeze of 28°F follows 9 days later, around November 6; in spring the one-in-ten date for 28°F is April 14, 12 days before the 32°F one. The freeze-free season lasts 201 days in a typical year, shorter than at 58% of the 144 Tennessee stations; it reaches 221 days one year in ten and falls short of 181 one year in ten. On average 84 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 April 22, and return around October 20. Severe cold of 16°F or below comes in 99% of winters, usually between December 23 and February 13.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 5 | Apr 11 | Apr 16 | Apr 19 | Apr 22 | Apr 26 | Apr 30 | May 4 | May 8 |
| 32°F | Mar 25 | Mar 30 | Apr 3 | Apr 6 | Apr 10 | Apr 13 | Apr 16 | Apr 20 | Apr 26 |
| 28°F | Mar 11 | Mar 17 | Mar 22 | Mar 26 | Mar 29 | Apr 1 | Apr 4 | Apr 8 | Apr 14 |
| 24°F | Feb 24 | Mar 2 | Mar 8 | Mar 12 | Mar 16 | Mar 20 | Mar 24 | Mar 28 | Apr 2 |
| 20°F | Feb 5 | Feb 14 | Feb 20 | Feb 27 | Mar 2 | Mar 6 | Mar 11 | Mar 16 | Mar 22 |
| 16°F99% of yrs | Jan 17 | Jan 28 | Feb 1 | Feb 6 | Feb 13 | Feb 19 | Feb 27 | Mar 4 | Mar 11 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 20 | Oct 22 | Oct 25 | Oct 28 | Nov 1 |
| 32°F | Oct 16 | Oct 20 | Oct 24 | Oct 26 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 9 |
| 28°F | Oct 26 | Oct 31 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 12 | Nov 16 | Nov 22 |
| 24°F | Nov 5 | Nov 9 | Nov 13 | Nov 15 | Nov 19 | Nov 22 | Nov 26 | Dec 1 | Dec 6 |
| 20°F | Nov 14 | Nov 19 | Nov 24 | Nov 28 | Dec 2 | Dec 5 | Dec 11 | Dec 20 | Dec 28 |
| 16°F99% of yrs | Nov 28 | Dec 5 | Dec 10 | Dec 16 | Dec 23 | Dec 28 | Jan 1 | Jan 7 | Jan 16 |
Freeze probabilities 1991–2020 at Morristown Radio Wcrk, 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 37811 →Compare Mooresburg with another place →
Weather by month in Mooresburg
July is the warmest month at Morristown Radio Wcrk, TN, averaging 86°F by day and 67°F at night; January is the coldest at 46°F and 27°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 75% of years.
Warmth for growing adds up to 4,129 growing degree days a year (base 50°F), fewer than at 74% of the 144 Tennessee stations. 38% of them (1,549) have built up by the end of June, and July adds the most, 826. Precipitation totals 48.2 inches a year, most in March (4.9") and least in October (2.8"); May to September bring 40% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 46 | 27 | 4.1 | 100% | 21 | 13 |
| Feb | 51 | 30 | 4.5 | 100% | 17 | 20 |
| Mar | 60 | 36 | 4.9 | 99% | 11 | 92 |
| Apr | 69 | 45 | 4.4 | 75% | 3 | 243 |
| May | 77 | 55 | 3.8 | 5% | 0 | 487 |
| Jun | 83 | 63 | 4.5 | 0% | 0 | 694 |
| Jul | 86 | 67 | 4.7 | 0% | 0 | 826 |
| Aug | 86 | 65 | 3.3 | 0% | 0 | 787 |
| Sep | 81 | 59 | 3.2 | 0% | 0 | 588 |
| Oct | 70 | 47 | 2.8 | 63% | 2 | 285 |
| Nov | 59 | 36 | 3.4 | 99% | 12 | 73 |
| Dec | 49 | 31 | 4.6 | 100% | 18 | 22 |
Monthly normals 1991–2020 at Morristown Radio Wcrk, TN (1,344 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, Rogersville 1 NE, TN, 14 miles east of Mooresburg, has a last frost 4 days later (April 14), a first frost 4 days earlier (October 24), a season 9 days shorter.
When it snows in Mooresburg, Tennessee
The first measurable snow (0.1 inch or more) in Mooresburg usually arrives around December 29, and the last of the season around March 1. Those are the middle dates across the winters of 1991–2020 at Morristown Radio Wcrk, TN, 11.6 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 40 days after the last snow.
Planting calendar for 37811
| When | What to do |
|---|---|
| January 30 – February 13 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 13 – February 27 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 13 – March 27 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 10 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 5 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 14 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 28 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 37811 is 12 miles from Morristown Radio Wcrk, TN, which stands at 1,344 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 37814 (Morristown). The 2023 USDA Plant Hardiness Zone Map lists ZIP 37811 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.