Skip to content

USDA Hardiness Zone 8a

Frost Dates for 37343 — Hixson, Tennessee

NOAA 1991–2020 normals from Soddy Daisy-Mowbray Mountain, TN (1,700 ft), 8 miles north.

Updated

In Hixson, the last spring frost (32°F) is around April 7 in half of years and has passed by April 28 in nine years out of ten. The first fall frost comes around October 29, as early as October 13 one year in ten, leaving a typical freeze-free season of 203 days (NOAA, Soddy Daisy-Mowbray Mountain, TN).

Last spring frost
April 7

50% probability

First fall frost
October 29

50% probability

Growing season
203 days

freeze-free, 50%

Hardiness zone
8a

10 to 15°F (-12.2 to -9.4°C) coldest night

First snow
January 17

median, 1991–2020

Last snow
February 24

median, 1991–2020

Winters with snow
94%

15 of 16 observed

Snow per year
4.3"

NOAA normal

Frost risk by date in Hixson

Half of springs at Soddy Daisy-Mowbray Mountain, TN see their last 32°F night by April 7; only one in ten is past it by March 20, and one in ten still has one after April 28. Planting tender crops after April 15 leaves a 30% risk of a frost on them, after April 20 20%, and after April 28 10%. The 21 days between the even-odds date and the one-in-ten date is the widest of the 144 Tennessee stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.

In fall the first 32°F night comes by October 29 in half of years, as early as October 13 one year in ten, and holds off past November 12 one year in ten. A hard freeze of 28°F follows 10 days later, around November 8; in spring the one-in-ten date for 28°F is April 13, 15 days before the 32°F one. The freeze-free season lasts 203 days in a typical year, shorter than at 52% of the 144 Tennessee stations; it reaches 229 days one year in ten and falls short of 178 one year in ten. On average 82 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 20, and return around October 20. Severe cold of 16°F or below comes in 97% of winters, usually between January 1 and February 15.

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

Freeze probabilities 1991–2020 at Soddy Daisy-Mowbray Mountain, 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 37343 →Compare Hixson with another place →

Weather by month in Hixson

July is the warmest month at Soddy Daisy-Mowbray Mountain, TN, averaging 88°F by day and 66°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 65% of years.

Warmth for growing adds up to 4,237 growing degree days a year (base 50°F), fewer than at 69% of the 144 Tennessee stations. 39% of them (1,635) have built up by the end of June, and July adds the most, 828. Precipitation totals 63.1 inches a year, most in December (6.8") and least in October (3.7"); May to September bring 39% of it.

Monthly normals 1991–2020 at Soddy Daisy-Mowbray Mountain, TN
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan48286.3100%2117
Feb51315.0100%1725
Mar61385.898%11113
Apr71475.865%3285
May78554.87%<1504
Jun85625.30%0691
Jul88664.90%0828
Aug87644.60%0793
Sep81575.02%0580
Oct70473.756%2291
Nov59385.199%977
Dec50326.8100%1834

Monthly normals 1991–2020 at Soddy Daisy-Mowbray Mountain, TN (1,700 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, Chattanooga Lovell Airport, TN, 9 miles south of Hixson and 1,029 feet lower, has a last frost 14 days earlier (March 24), a first frost 11 days later (November 9), a season 27 days longer.

Frost dates for 37421 (Chattanooga) →

When it snows in Hixson, Tennessee

The first measurable snow (0.1 inch or more) in Hixson usually arrives around January 17, and the last of the season around February 24. Those are the middle dates across the winters of 1991–2020 at Soddy Daisy-Mowbray Mountain, TN, 7.9 miles away: half of years saw snow earlier, half later. Snow fell in 94% of those winters. The last 32°F night of spring typically comes 42 days after the last snow.

Planting calendar for 37343

What to do and when, from the 50% frost dates for Hixson, Tennessee
WhenWhat to do
January 27 – February 10Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 10 – February 24Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 10 – March 24Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 7 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by August 6Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 15Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 29 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 37343 is 8 miles from Soddy Daisy-Mowbray Mountain, TN, which stands at 1,700 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 37343 in zone 8a, the band where the coldest night of the year averaged 10 to 15°F (-12.2 to -9.4°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 8a places in Tennessee