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USDA Hardiness Zone 7b

Frost Dates for 38305 — Jackson, Tennessee

NOAA 1991–2020 normals from Jackson 4 NE, TN (430 ft), 2 miles northwest.

Updated

In Jackson, the last spring frost (32°F) is around April 4 in half of years and has passed by April 21 in nine years out of ten. The first fall frost comes around October 30, as early as October 18 one year in ten, leaving a typical freeze-free season of 208 days (NOAA, Jackson 4 NE, TN).

Last spring frost
April 4

50% probability

First fall frost
October 30

50% probability

Growing season
208 days

freeze-free, 50%

Hardiness zone
7b

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

First snow
January 12

median, 1991–2020

Last snow
February 16

median, 1991–2020

Winters with snow
100%

15 of 15 observed

Snow per year
4.4"

NOAA normal

Frost risk by date in Jackson

Half of springs at Jackson 4 NE, TN see their last 32°F night by April 4; only one in ten is past it by March 18, and one in ten still has one after April 21. Planting tender crops after April 11 leaves a 30% risk of a frost on them, after April 16 20%, and after April 21 10%. The 17 days between the even-odds date and the one-in-ten date is narrower than at 34% of the 144 Tennessee stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 30 in half of years, as early as October 18 one year in ten, and holds off past November 13 one year in ten. A hard freeze of 28°F follows 9 days later, around November 8; in spring the one-in-ten date for 28°F is April 11, 10 days before the 32°F one. The freeze-free season lasts 208 days in a typical year, longer than at 61% of the 144 Tennessee stations; it reaches 230 days one year in ten and falls short of 188 one year in ten. On average 79 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 16, and return around October 22. Severe cold of 16°F or below comes in 97% of winters, usually between December 23 and February 12.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FMar 31Apr 5Apr 9Apr 13Apr 16Apr 20Apr 23Apr 27May 1
32°FMar 18Mar 24Mar 30Apr 2Apr 4Apr 7Apr 11Apr 16Apr 21
28°FMar 4Mar 11Mar 16Mar 20Mar 24Mar 29Apr 2Apr 5Apr 11
24°FFeb 19Feb 26Mar 2Mar 6Mar 11Mar 15Mar 19Mar 26Apr 2
20°FFeb 3Feb 12Feb 19Feb 24Feb 28Mar 2Mar 7Mar 13Mar 21
16°F97% of yrsJan 12Jan 25Jan 31Feb 6Feb 12Feb 19Feb 25Mar 1Mar 9
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FOct 10Oct 14Oct 17Oct 20Oct 22Oct 24Oct 26Oct 29Nov 3
32°FOct 18Oct 22Oct 25Oct 28Oct 30Nov 1Nov 4Nov 8Nov 13
28°FOct 27Oct 31Nov 3Nov 5Nov 8Nov 11Nov 15Nov 21Nov 28
24°FNov 5Nov 9Nov 13Nov 17Nov 21Nov 25Nov 29Dec 2Dec 9
20°FNov 14Nov 20Nov 26Dec 1Dec 3Dec 7Dec 12Dec 18Dec 28
16°F97% of yrsNov 30Dec 4Dec 10Dec 16Dec 23Dec 28Jan 2Jan 9Jan 20

Freeze probabilities 1991–2020 at Jackson 4 NE, 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 38305 →Compare Jackson with another place →

Weather by month in Jackson

July is the warmest month at Jackson 4 NE, TN, averaging 90°F by day and 69°F at night; January is the coldest at 48°F and 28°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 63% of years.

Warmth for growing adds up to 4,765 growing degree days a year (base 50°F), more than at 82% of the 144 Tennessee stations. 39% of them (1,848) have built up by the end of June, and July adds the most, 922. Precipitation totals 55.1 inches a year, most in May (6.0") and least in August (3.5"); May to September bring 40% of it.

Monthly normals 1991–2020 at Jackson 4 NE, TN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan48284.3100%2126
Feb52304.6100%1740
Mar61385.798%10124
Apr72475.063%1303
May79576.01%0568
Jun87664.70%0787
Jul90694.30%0922
Aug90673.50%0885
Sep84603.70%0649
Oct73483.856%2332
Nov60374.299%1196
Dec50315.3100%1832

Monthly normals 1991–2020 at Jackson 4 NE, TN (430 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, Jackson Exp Stn, TN, 5 miles southwest of Jackson, has a last frost 2 days earlier (April 2), a first frost 1 day earlier (October 29), a season 1 day shorter.

Frost dates for 38301 (Jackson) →

When it snows in Jackson, Tennessee

The first measurable snow (0.1 inch or more) in Jackson usually arrives around January 12, and the last of the season around February 16. Those are the middle dates across the winters of 1991–2020 at Jackson 4 NE, TN, 1.5 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 47 days after the last snow.

Planting calendar for 38305

What to do and when, from the 50% frost dates for Jackson, Tennessee
WhenWhat to do
January 24 – February 7Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 7 – February 21Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 7 – March 21Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 4 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by August 7Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 16Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 30 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 38305 is 2 miles from Jackson 4 NE, TN, which stands at 430 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 38305 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