USDA Hardiness Zone 8a
Frost Dates for 27517 — Chapel Hill, North Carolina
NOAA 1991–2020 normals from Chapel Hill 2 W, NC (500 ft), 4 miles west.
Updated
In Chapel Hill, the last spring frost (32°F) is around March 31 in half of years and has passed by April 14 in nine years out of ten. The first fall frost comes around November 3, as early as October 23 one year in ten, leaving a typical freeze-free season of 218 days (NOAA, Chapel Hill 2 W, NC).
- Last spring frost
- March 31
- First fall frost
- November 3
- 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
- January 17
- Last snow
- February 11
- Winters with snow
- 55%
- Snow per year
- 2.8"
median, 1991–2020
median, 1991–2020
11 of 20 observed
NOAA normal
Frost risk by date in Chapel Hill
Half of springs at Chapel Hill 2 W, NC see their last 32°F night by March 31; only one in ten is past it by March 16, and one in ten still has one after April 14. Planting tender crops after April 5 leaves a 30% risk of a frost on them, after April 8 20%, and after April 14 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 79% of the 173 North Carolina stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 3 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 11 days later, around November 14; in spring the one-in-ten date for 28°F is April 1, 13 days before the 32°F one. The freeze-free season lasts 218 days in a typical year, longer than at 51% of the 173 North Carolina stations; it reaches 238 days one year in ten and falls short of 200 one year in ten. On average 77 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 14 days longer, to about April 14, and return around October 26. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 83%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 31 | Apr 4 | Apr 8 | Apr 11 | Apr 14 | Apr 18 | Apr 20 | Apr 24 | Apr 30 |
| 32°F | Mar 16 | Mar 21 | Mar 25 | Mar 28 | Mar 31 | Apr 2 | Apr 5 | Apr 8 | Apr 14 |
| 28°F | Mar 1 | Mar 7 | Mar 11 | Mar 15 | Mar 19 | Mar 22 | Mar 26 | Mar 29 | Apr 1 |
| 24°F | Feb 9 | Feb 19 | Feb 26 | Mar 1 | Mar 4 | Mar 8 | Mar 13 | Mar 17 | Mar 24 |
| 20°F98% of yrs | Jan 19 | Jan 30 | Feb 3 | Feb 10 | Feb 16 | Feb 23 | Mar 1 | Mar 6 | Mar 13 |
| 16°F83% of yrs | Jan 3 | Jan 11 | Jan 19 | Jan 24 | Jan 30 | Feb 2 | Feb 7 | Feb 19 | Mar 2 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 14 | Oct 18 | Oct 21 | Oct 24 | Oct 26 | Oct 28 | Oct 31 | Nov 2 | Nov 6 |
| 32°F | Oct 23 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 13 | Nov 19 |
| 28°F | Nov 1 | Nov 5 | Nov 7 | Nov 11 | Nov 14 | Nov 17 | Nov 22 | Nov 27 | Dec 3 |
| 24°F | Nov 11 | Nov 17 | Nov 22 | Nov 27 | Dec 1 | Dec 4 | Dec 9 | Dec 17 | Dec 30 |
| 20°F98% of yrs | Nov 26 | Dec 2 | Dec 7 | Dec 12 | Dec 21 | Dec 27 | Jan 1 | Jan 8 | Jan 18 |
| 16°F83% of yrs | Dec 11 | Dec 20 | Dec 28 | Jan 1 | Jan 6 | Jan 11 | Jan 16 | Jan 22 | Feb 1 |
Freeze probabilities 1991–2020 at Chapel Hill 2 W, NC, 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 27517 →Compare Chapel Hill with another place →
Weather by month in Chapel Hill
July is the warmest month at Chapel Hill 2 W, NC, averaging 90°F by day and 69°F at night; January is the coldest at 51°F and 29°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 46% of years.
Warmth for growing adds up to 4,671 growing degree days a year (base 50°F), more than at 52% of the 173 North Carolina stations. 38% of them (1,776) have built up by the end of June, and July adds the most, 911. Precipitation totals 49.0 inches a year, most in September (5.4") and least in February (3.3"); May to September bring 46% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 51 | 29 | 4.0 | 100% | 21 | 25 |
| Feb | 54 | 31 | 3.3 | 100% | 17 | 34 |
| Mar | 62 | 38 | 4.4 | 97% | 10 | 120 |
| Apr | 72 | 47 | 3.7 | 46% | 1 | 295 |
| May | 79 | 56 | 3.8 | 0% | 0 | 542 |
| Jun | 86 | 65 | 4.1 | 0% | 0 | 760 |
| Jul | 90 | 69 | 4.8 | 0% | 0 | 911 |
| Aug | 88 | 68 | 4.3 | 0% | 0 | 856 |
| Sep | 82 | 62 | 5.4 | 0% | 0 | 649 |
| Oct | 72 | 49 | 3.8 | 36% | 1 | 331 |
| Nov | 62 | 38 | 3.5 | 98% | 10 | 107 |
| Dec | 54 | 32 | 3.9 | 99% | 18 | 41 |
Monthly normals 1991–2020 at Chapel Hill 2 W, NC (500 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, Chapel Hill Williams Airport, NC, 4 miles northwest of Chapel Hill, has a last frost 2 days earlier (March 29), a first frost 2 days later (November 5), a season 4 days longer.
When it snows in Chapel Hill, North Carolina
The first measurable snow (0.1 inch or more) in Chapel Hill usually arrives around January 17, and the last of the season around February 11. Those are the middle dates across the winters of 1991–2020 at Chapel Hill 2 W, NC, 3.5 miles away: half of years saw snow earlier, half later. Snow fell in 55% of those winters. The last 32°F night of spring typically comes 48 days after the last snow.
Planting calendar for 27517
| 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 11 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 20 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 3 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 27517 is 4 miles from Chapel Hill 2 W, NC, which stands at 500 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 27516 (Chapel Hill). The 2023 USDA Plant Hardiness Zone Map lists ZIP 27517 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 North 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.