USDA Hardiness Zone 8a
Frost Dates for 29708 — Fort Mill, South Carolina
NOAA 1991–2020 normals from Rock Hill York Co Airport, SC (669 ft), 5 miles southwest.
Updated
In Fort Mill, the last spring frost (32°F) is around March 31 in half of years and has passed by April 15 in nine years out of ten. The first fall frost comes around November 4, as early as October 23 one year in ten, leaving a typical freeze-free season of 218 days (NOAA, Rock Hill York Co Airport, SC).
- Last spring frost
- March 31
- First fall frost
- November 4
- Growing season
- 218 days
- Hardiness zone
- 8a
50% probability
50% probability
freeze-free, 50%
10 to 15°F (-12.2 to -9.4°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 10%
- Snow per year
- 0.2"
median, 1991–2020
median, 1991–2020
2 of 20 observed
NOAA normal
Frost risk by date in Fort Mill
Half of springs at Rock Hill York Co Airport, SC see their last 32°F night by March 31; only one in ten is past it by March 13, and one in ten still has one after April 15. Planting tender crops after April 6 leaves a 30% risk of a frost on them, after April 9 20%, and after April 15 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 66% of the 105 South Carolina stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 4 in half of years, as early as October 23 one year in ten, and holds off past November 19 one year in ten. A hard freeze of 28°F follows 12 days later, around November 16; in spring the one-in-ten date for 28°F is April 4, 11 days before the 32°F one. The freeze-free season lasts 218 days in a typical year, shorter than at 80% of the 105 South Carolina stations; it reaches 241 days one year in ten and falls short of 199 one year in ten. On average 65 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 13, and return around October 26. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 84%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 29 | Apr 2 | Apr 6 | Apr 9 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 28 |
| 32°F | Mar 13 | Mar 18 | Mar 23 | Mar 27 | Mar 31 | Apr 2 | Apr 6 | Apr 9 | Apr 15 |
| 28°F | Feb 27 | Mar 5 | Mar 11 | Mar 15 | Mar 18 | Mar 22 | Mar 26 | Mar 30 | Apr 4 |
| 24°F | Feb 8 | Feb 18 | Feb 24 | Feb 28 | Mar 4 | Mar 9 | Mar 14 | Mar 19 | Mar 26 |
| 20°F99% of yrs | Jan 20 | Jan 30 | Feb 4 | Feb 10 | Feb 17 | Feb 23 | Feb 28 | Mar 6 | Mar 14 |
| 16°F84% of yrs | Jan 2 | Jan 11 | Jan 19 | Jan 27 | Jan 31 | Feb 4 | Feb 12 | Feb 21 | Mar 3 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 14 | Oct 18 | Oct 21 | Oct 24 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 7 |
| 32°F | Oct 23 | Oct 27 | Oct 31 | Nov 1 | Nov 4 | Nov 6 | Nov 10 | Nov 13 | Nov 19 |
| 28°F | Nov 1 | Nov 6 | Nov 9 | Nov 13 | Nov 16 | Nov 19 | Nov 24 | Nov 29 | Dec 4 |
| 24°F | Nov 13 | Nov 18 | Nov 23 | Nov 28 | Dec 1 | Dec 5 | Dec 9 | Dec 19 | Dec 29 |
| 20°F99% of yrs | Nov 27 | Dec 3 | Dec 6 | Dec 13 | Dec 21 | Dec 29 | Jan 2 | Jan 7 | Jan 15 |
| 16°F84% of yrs | Dec 8 | Dec 19 | Dec 27 | Jan 1 | Jan 5 | Jan 10 | Jan 14 | Jan 21 | Feb 1 |
Freeze probabilities 1991–2020 at Rock Hill York Co Airport, SC, 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 29708 →Compare Fort Mill with another place →
Weather by month in Fort Mill
July is the warmest month at Rock Hill York Co Airport, SC, averaging 90°F by day and 69°F at night; January is the coldest at 52°F and 31°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 47% of years.
Warmth for growing adds up to 4,934 growing degree days a year (base 50°F), fewer than at 81% of the 105 South Carolina stations. 39% of them (1,940) have built up by the end of June, and July adds the most, 922. Precipitation totals 42.6 inches a year, most in June (4.0") and least in October (3.0"); May to September bring 44% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 52 | 31 | 3.5 | 100% | 19 | 34 |
| Feb | 57 | 34 | 3.2 | 100% | 14 | 51 |
| Mar | 64 | 40 | 3.8 | 95% | 7 | 152 |
| Apr | 74 | 48 | 3.6 | 47% | 1 | 333 |
| May | 80 | 57 | 3.2 | 0% | 0 | 578 |
| Jun | 87 | 66 | 4.0 | 0% | 0 | 792 |
| Jul | 90 | 69 | 4.0 | 0% | 0 | 922 |
| Aug | 89 | 68 | 4.0 | 0% | 0 | 880 |
| Sep | 83 | 62 | 3.4 | 0% | 0 | 670 |
| Oct | 73 | 49 | 3.0 | 33% | 1 | 360 |
| Nov | 63 | 39 | 3.3 | 98% | 8 | 114 |
| Dec | 55 | 33 | 3.6 | 99% | 16 | 48 |
Monthly normals 1991–2020 at Rock Hill York Co Airport, SC (669 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, Winthrop Univ, SC, 7 miles south of Fort Mill, has a last frost 4 days earlier (March 27), a first frost 1 day later (November 5), a season 7 days longer.
When it snows in Fort Mill, South Carolina
Measurable snow is rare here: only 2 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Fort Mill 4 NW, SC, 1.5 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 29708
| When | What to do |
|---|---|
| January 20 – February 3 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 3 – February 17 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 3 – March 17 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| March 31 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 12 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 21 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 4 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 29708 is 5 miles from Rock Hill York Co Airport, SC, which stands at 669 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 29732 (Rock Hill). The 2023 USDA Plant Hardiness Zone Map lists ZIP 29708 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 South Carolina →
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.