Skip to content

USDA Hardiness Zone 6b

Frost Dates for 47170 — Scottsburg, Indiana

NOAA 1991–2020 normals from Scottsburg, IN (570 ft), 1 miles east.

Updated

In Scottsburg, the last spring frost (32°F) is around April 18 in half of years and has passed by May 3 in nine years out of ten. The first fall frost comes around October 20, as early as October 6 one year in ten, leaving a typical freeze-free season of 185 days (NOAA, Scottsburg, IN).

Last spring frost
April 18

50% probability

First fall frost
October 20

50% probability

Growing season
185 days

freeze-free, 50%

Hardiness zone
6b

-5 to 0°F (-20.6 to -17.8°C) coldest night

First snow
December 21

median, 1991–2020

Last snow
February 27

median, 1991–2020

Winters with snow
100%

16 of 16 observed

Snow per year
—

NOAA normal

Frost risk by date in Scottsburg

Half of springs at Scottsburg, IN see their last 32°F night by April 18; only one in ten is past it by April 4, and one in ten still has one after May 3. Planting tender crops after April 24 leaves a 30% risk of a frost on them, after April 28 20%, and after May 3 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 70% of the 125 Indiana stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 20 in half of years, as early as October 6 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 12 days later, around November 1; in spring the one-in-ten date for 28°F is April 21, 12 days before the 32°F one. The freeze-free season lasts 185 days in a typical year, longer than at 58% of the 125 Indiana stations; it reaches 205 days one year in ten and falls short of 164 one year in ten. On average 114 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 11 days longer, to about April 29, and return around October 11. Severe cold of 16°F or below comes every winter, usually between December 5 and March 1.

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

Freeze probabilities 1991–2020 at Scottsburg, IN, 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 47170 →Compare Scottsburg with another place →

Frost risk through the year in Scottsburg

Frost curve for Scottsburg, Indiana (Scottsburg, IN, NOAA 1991–2020): the chance of another 32°F night falls from 90% on April 4 to 50% on April 18 and 10% on May 3; the chance that the first fall one has come rises from 10% on October 6 to 50% on October 20 and 90% on November 1.

In Scottsburg, the spring curve drops under 10% on May 3 and the fall curve passes 10% on October 6, 156 days later; that gap is longer than at 60% of the 125 Indiana stations with frost dates. The spring risk falls from 90% to 10% over 29 days (April 4 to May 3) and the fall risk climbs from 10% to 90% over 26 days (October 6 to November 1): both ends of the season vary about as much. At Salem, IN, 16 miles west, the same gap runs from May 4 to October 7, the same length.

Chance of a frost after each planting date in Scottsburg
Planted onAnother 32°F night28°F night
Apr 4over 90%53%
Apr 1173%33%
Apr 1850% date50%15%
Apr 2528%under 10%
May 212%under 10%
May 9under 10%under 10%

Weather by month in Scottsburg

July is the warmest month at Scottsburg, IN, averaging 88°F by day and 66°F at night; January is the coldest at 41°F and 23°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 15% of years.

Warmth for growing adds up to 3,858 growing degree days a year (base 50°F), more than at 79% of the 125 Indiana stations. 37% of them (1,441) have built up by the end of June, and July adds the most, 821.

Monthly normals 1991–2020 at Scottsburg, IN
MonthHigh °FLow °F32°F nightNights ≤ 32°FGDD 50°F
Jan4123100%258
Feb4525100%239
Mar563299%1860
Apr684293%5206
May765315%<1457
Jun85620%0700
Jul88660%0821
Aug87630%0764
Sep81542%<1530
Oct694386%5225
Nov5633100%1564
Dec4527100%2312

Monthly normals 1991–2020 at Scottsburg, IN (570 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, Salem, IN, 16 miles west of Scottsburg and 215 feet higher, has a last frost 1 day earlier (April 17), a first frost 2 days later (October 22), a season 1 day longer.

Frost dates for 47167 (Salem) →

When it snows in Scottsburg, Indiana

The first measurable snow (0.1 inch or more) in Scottsburg usually arrives around December 21, and the last of the season around February 27. Those are the middle dates across the winters of 1991–2020 at Scottsburg, IN, 1 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 50 days after the last snow.

Planting calendar for 47170

What to do and when, from the 50% frost dates for Scottsburg, Indiana
WhenWhat to do
February 7 – February 21Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 21 – March 7Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 21 – April 4Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 18 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 28Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 6Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 20 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 47170 is 1 mile from Scottsburg, IN, which stands at 570 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 47170 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Indiana →

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 6b places in Indiana