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USDA Hardiness Zone 7b

Frost Dates for 37179 — Thompsons Station, Tennessee

NOAA 1991–2020 normals from Thompson Stn, TN (775 ft), 3 miles southwest.

Updated

In Thompsons Station, the last spring frost (32°F) is around April 3 in half of years and has passed by April 22 in nine years out of ten. The first fall frost comes around November 1, as early as October 20 one year in ten, leaving a typical freeze-free season of 211 days (NOAA, Thompson Stn, TN).

Last spring frost
April 3

50% probability

First fall frost
November 1

50% probability

Growing season
211 days

freeze-free, 50%

Hardiness zone
7b

5 to 10°F (-15.0 to -12.2°C) coldest night

First snow
January 6

median, 1991–2020

Last snow
February 27

median, 1991–2020

Winters with snow
100%

18 of 18 observed

Snow per year
3.5"

NOAA normal

Frost risk by date in Thompsons Station

Half of springs at Thompson Stn, TN see their last 32°F night by April 3; only one in ten is past it by March 17, and one in ten still has one after April 22. Planting tender crops after April 10 leaves a 30% risk of a frost on them, after April 15 20%, and after April 22 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 November 1 in half of years, as early as October 20 one year in ten, and holds off past November 15 one year in ten. A hard freeze of 28°F follows 10 days later, around November 11; in spring the one-in-ten date for 28°F is April 11, 11 days before the 32°F one. The freeze-free season lasts 211 days in a typical year, longer than at 74% of the 144 Tennessee stations; it reaches 233 days one year in ten and falls short of 190 one year in ten. On average 80 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 14 days longer, to about April 17, and return around October 23. Severe cold of 16°F or below comes in 98% of winters, usually between December 24 and February 11.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 1Apr 6Apr 10Apr 14Apr 17Apr 20Apr 24Apr 28May 2
32°FMar 17Mar 22Mar 28Mar 31Apr 3Apr 6Apr 10Apr 15Apr 22
28°FMar 2Mar 8Mar 14Mar 18Mar 23Mar 26Mar 31Apr 3Apr 11
24°FFeb 17Feb 25Feb 28Mar 4Mar 8Mar 13Mar 17Mar 23Apr 1
20°FFeb 3Feb 11Feb 16Feb 21Feb 25Mar 1Mar 4Mar 10Mar 16
16°F98% of yrsJan 18Jan 26Jan 31Feb 5Feb 11Feb 16Feb 21Feb 26Mar 5
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FOct 11Oct 15Oct 18Oct 20Oct 23Oct 25Oct 28Oct 31Nov 4
32°FOct 20Oct 24Oct 27Oct 31Nov 1Nov 4Nov 7Nov 10Nov 15
28°FOct 30Nov 2Nov 5Nov 8Nov 11Nov 15Nov 18Nov 23Nov 30
24°FNov 6Nov 12Nov 16Nov 20Nov 24Nov 28Dec 1Dec 6Dec 14
20°FNov 15Nov 23Nov 28Dec 2Dec 6Dec 10Dec 15Dec 22Dec 29
16°F98% of yrsDec 1Dec 6Dec 11Dec 18Dec 24Dec 29Jan 2Jan 8Jan 18

Freeze probabilities 1991–2020 at Thompson Stn, 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 37179 →Compare Thompsons Station with another place →

Weather by month in Thompsons Station

July is the warmest month at Thompson Stn, TN, averaging 89°F by day and 69°F at night; January is the coldest at 48°F and 29°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 59% of years.

Warmth for growing adds up to 4,827 growing degree days a year (base 50°F), more than at 85% of the 144 Tennessee stations. 38% of them (1,845) have built up by the end of June, and July adds the most, 911. Precipitation totals 55.9 inches a year, most in December (5.8") and least in August (3.6"); May to September bring 39% of it.

Monthly normals 1991–2020 at Thompson Stn, TN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan48294.6100%2125
Feb51325.2100%1738
Mar61395.098%9126
Apr71475.359%2301
May79575.11%0565
Jun87664.60%0790
Jul89694.60%0911
Aug89693.60%0896
Sep84624.10%0684
Oct73493.844%2351
Nov61384.299%10103
Dec51325.8100%1838

Monthly normals 1991–2020 at Thompson Stn, TN (775 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, Franklin Sewage Plt, TN, 10 miles north of Thompsons Station, has the same 50% last-frost date, a first frost 1 day earlier (October 31), a season 1 day shorter.

Frost dates for 37064 (Franklin) →

When it snows in Thompsons Station, Tennessee

The first measurable snow (0.1 inch or more) in Thompsons Station usually arrives around January 6, and the last of the season around February 27. Those are the middle dates across the winters of 1991–2020 at Thompson Stn, TN, 2.8 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 35 days after the last snow.

Planting calendar for 37179

What to do and when, from the 50% frost dates for Thompsons Station, Tennessee
WhenWhat to do
January 23 – February 6Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 6 – February 20Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 6 – March 20Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 3 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by August 9Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 18Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
November 1 onwardPlant 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 37179 is 3 miles from Thompson Stn, TN, which stands at 775 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 37174 (Spring Hill). The 2023 USDA Plant Hardiness Zone Map lists ZIP 37179 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.

ZIP codes measured at the same station

Other zone 7b places in Tennessee