USDA Hardiness Zone 7a
Frost Dates for 42330 — Central City, Kentucky
NOAA 1991–2020 normals from Rochester Ferry, KY (390 ft), 14 miles southeast.
Updated
In Central City, the last spring frost (32°F) is around April 15 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 9 one year in ten, leaving a typical freeze-free season of 187 days (NOAA, Rochester Ferry, KY).
- Last spring frost
- April 15
- First fall frost
- October 20
- Growing season
- 187 days
- Hardiness zone
- 7a
50% probability
50% probability
freeze-free, 50%
0 to 5°F (-17.8 to -15.0°C) coldest night
- First snow
- December 23
- Last snow
- February 26
- Winters with snow
- 94%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
15 of 16 observed
NOAA normal
Frost risk by date in Central City
Half of springs at Rochester Ferry, KY see their last 32°F night by April 15; only one in ten is past it by March 31, and one in ten still has one after May 3. Planting tender crops after April 23 leaves a 30% risk of a frost on them, after April 27 20%, and after May 3 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 54% of the 113 Kentucky 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 9 one year in ten, and holds off past October 30 one year in ten. A hard freeze of 28°F follows 10 days later, around October 30; in spring the one-in-ten date for 28°F is April 19, 14 days before the 32°F one. The freeze-free season lasts 187 days in a typical year, shorter than at 72% of the 113 Kentucky stations; it reaches 207 days one year in ten and falls short of 168 one year in ten. On average 97 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 27, and return around October 12. Severe cold of 16°F or below comes every winter, usually between December 6 and February 26.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 12 | Apr 17 | Apr 20 | Apr 23 | Apr 27 | Apr 30 | May 3 | May 7 | May 12 |
| 32°F | Mar 31 | Apr 5 | Apr 8 | Apr 12 | Apr 15 | Apr 19 | Apr 23 | Apr 27 | May 3 |
| 28°F | Mar 17 | Mar 24 | Mar 28 | Mar 31 | Apr 2 | Apr 4 | Apr 8 | Apr 12 | Apr 19 |
| 24°F | Mar 2 | Mar 9 | Mar 14 | Mar 18 | Mar 21 | Mar 25 | Mar 29 | Apr 1 | Apr 6 |
| 20°F | Feb 16 | Feb 25 | Feb 28 | Mar 4 | Mar 8 | Mar 13 | Mar 17 | Mar 21 | Mar 28 |
| 16°F | Feb 2 | Feb 9 | Feb 15 | Feb 20 | Feb 26 | Mar 1 | Mar 5 | Mar 10 | Mar 17 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 5 | Oct 8 | Oct 10 | Oct 12 | Oct 14 | Oct 16 | Oct 18 | Oct 21 |
| 32°F | Oct 9 | Oct 13 | Oct 15 | Oct 18 | Oct 20 | Oct 22 | Oct 24 | Oct 27 | Oct 30 |
| 28°F | Oct 18 | Oct 22 | Oct 25 | Oct 28 | Oct 30 | Nov 1 | Nov 4 | Nov 8 | Nov 13 |
| 24°F | Oct 31 | Nov 3 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 19 | Nov 23 | Dec 1 |
| 20°F | Nov 6 | Nov 12 | Nov 16 | Nov 19 | Nov 23 | Nov 27 | Dec 1 | Dec 5 | Dec 13 |
| 16°F | Nov 15 | Nov 22 | Nov 28 | Dec 1 | Dec 6 | Dec 10 | Dec 15 | Dec 22 | Dec 29 |
Freeze probabilities 1991–2020 at Rochester Ferry, KY, 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 42330 →Compare Central City with another place →
Weather by month in Central City
July is the warmest month at Rochester Ferry, KY, averaging 89°F by day and 65°F at night; January is the coldest at 44°F and 24°F. A freezing night is all but certain in every month from October to March (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 88% of years and May still brings one in 14% of years.
Warmth for growing adds up to 4,018 growing degree days a year (base 50°F), more than at 50% of the 113 Kentucky stations. 37% of them (1,498) have built up by the end of June, and July adds the most, 840. Precipitation totals 51.1 inches a year, most in April (5.1") and least in January (3.4"); May to September bring 43% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 44 | 24 | 3.4 | 100% | 24 | 10 |
| Feb | 48 | 26 | 4.0 | 100% | 20 | 16 |
| Mar | 58 | 34 | 4.2 | 100% | 14 | 72 |
| Apr | 69 | 43 | 5.1 | 88% | 4 | 229 |
| May | 78 | 53 | 5.1 | 14% | <1 | 473 |
| Jun | 86 | 61 | 4.7 | 0% | 0 | 697 |
| Jul | 89 | 65 | 4.7 | 0% | 0 | 840 |
| Aug | 88 | 63 | 3.9 | 0% | 0 | 790 |
| Sep | 82 | 56 | 3.6 | 1% | 0 | 560 |
| Oct | 71 | 43 | 4.1 | 93% | 2 | 252 |
| Nov | 58 | 34 | 3.8 | 100% | 14 | 65 |
| Dec | 48 | 27 | 4.5 | 100% | 20 | 13 |
Monthly normals 1991–2020 at Rochester Ferry, KY (390 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, Beaver Dam, KY, 16 miles northeast of Central City, has a last frost 5 days earlier (April 10), a first frost 2 days later (October 22), a season 5 days longer.
When it snows in Central City, Kentucky
The first measurable snow (0.1 inch or more) in Central City usually arrives around December 23, and the last of the season around February 26. Those are the middle dates across the winters of 1991–2020 at Beaver Dam, KY, 16 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 48 days after the last snow.
Planting calendar for 42330
| When | What to do |
|---|---|
| February 4 – February 18 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 18 – March 4 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 18 – April 1 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 15 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 42330 is 14 miles from Rochester Ferry, KY, which stands at 390 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 42345 (Greenville). The 2023 USDA Plant Hardiness Zone Map lists ZIP 42330 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°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.