USDA Hardiness Zone 6b
Frost Dates for 47138 — Lexington, Indiana
NOAA 1991–2020 normals from Scottsburg, IN (570 ft), 10 miles west.
Updated
In Lexington, 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
- First fall frost
- October 20
- Growing season
- 185 days
- Hardiness zone
- 6b
50% probability
50% probability
freeze-free, 50%
-5 to 0°F (-20.6 to -17.8°C) coldest night
- First snow
- December 21
- Last snow
- February 27
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
16 of 16 observed
NOAA normal
Frost risk by date in Lexington
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.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 15 | Apr 19 | Apr 23 | Apr 25 | Apr 29 | May 1 | May 4 | May 8 | May 13 |
| 32°F | Apr 4 | Apr 8 | Apr 12 | Apr 15 | Apr 18 | Apr 21 | Apr 24 | Apr 28 | May 3 |
| 28°F | Mar 20 | Mar 26 | Mar 31 | Apr 2 | Apr 5 | Apr 8 | Apr 12 | Apr 15 | Apr 21 |
| 24°F | Mar 4 | Mar 12 | Mar 17 | Mar 21 | Mar 25 | Mar 28 | Mar 31 | Apr 3 | Apr 9 |
| 20°F | Feb 18 | Feb 26 | Mar 3 | Mar 9 | Mar 13 | Mar 17 | Mar 20 | Mar 25 | Mar 30 |
| 16°F | Feb 6 | Feb 13 | Feb 19 | Feb 25 | Mar 1 | Mar 5 | Mar 10 | Mar 14 | Mar 20 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 29 | Oct 2 | Oct 6 | Oct 8 | Oct 11 | Oct 13 | Oct 15 | Oct 18 | Oct 22 |
| 32°F | Oct 6 | Oct 11 | Oct 15 | Oct 18 | Oct 20 | Oct 23 | Oct 25 | Oct 29 | Nov 1 |
| 28°F | Oct 19 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 15 |
| 24°F | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 19 | Nov 24 | Nov 30 |
| 20°F | Nov 7 | Nov 12 | Nov 17 | Nov 21 | Nov 25 | Nov 29 | Dec 1 | Dec 6 | Dec 13 |
| 16°F | Nov 15 | Nov 23 | Nov 29 | Dec 1 | Dec 5 | Dec 10 | Dec 16 | Dec 22 | Dec 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 47138 →Compare Lexington with another place →
Weather by month in Lexington
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.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 41 | 23 | 100% | 25 | 8 |
| Feb | 45 | 25 | 100% | 23 | 9 |
| Mar | 56 | 32 | 99% | 18 | 60 |
| Apr | 68 | 42 | 93% | 5 | 206 |
| May | 76 | 53 | 15% | <1 | 457 |
| Jun | 85 | 62 | 0% | 0 | 700 |
| Jul | 88 | 66 | 0% | 0 | 821 |
| Aug | 87 | 63 | 0% | 0 | 764 |
| Sep | 81 | 54 | 2% | <1 | 530 |
| Oct | 69 | 43 | 86% | 5 | 225 |
| Nov | 56 | 33 | 100% | 15 | 64 |
| Dec | 45 | 27 | 100% | 23 | 12 |
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, Madison Sewage Plt, IN, 12 miles east of Lexington, has a last frost 7 days earlier (April 11), a first frost 11 days later (October 31), a season 16 days longer.
When it snows in Lexington, Indiana
The first measurable snow (0.1 inch or more) in Lexington 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, 9.5 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 50 days after the last snow.
Planting calendar for 47138
| When | What to do |
|---|---|
| February 7 – February 21 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 21 – March 7 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 21 – April 4 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 18 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 28 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 6 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 20 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 47138 is 10 miles 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; its figures are presented in full for 47170 (Scottsburg). The 2023 USDA Plant Hardiness Zone Map lists ZIP 47138 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.
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.