USDA Hardiness Zone 8a
Frost Dates for 27539 — Apex, North Carolina
NOAA 1991–2020 normals from Cary, NC (390 ft), 3 miles north.
Updated
In Apex, the last spring frost (32°F) is around March 31 in half of years and has passed by April 12 in nine years out of ten. The first fall frost comes around November 10, as early as October 30 one year in ten, leaving a typical freeze-free season of 226 days (NOAA, Cary, NC).
- Last spring frost
- March 31
- First fall frost
- November 10
- Growing season
- 226 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
- 35%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
7 of 20 observed
NOAA normal
Frost risk by date in Apex
Half of springs at Cary, NC see their last 32°F night by March 31; only one in ten is past it by March 12, and one in ten still has one after April 12. Planting tender crops after April 4 leaves a 30% risk of a frost on them, after April 7 20%, and after April 12 10%. The 12 days between the even-odds date and the one-in-ten date is narrower than at 98% of the 173 North Carolina stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 10 in half of years, as early as October 30 one year in ten, and holds off past November 27 one year in ten. A hard freeze of 28°F follows 14 days later, around November 24; in spring the one-in-ten date for 28°F is April 2, 10 days before the 32°F one. The freeze-free season lasts 226 days in a typical year, longer than at 68% of the 173 North Carolina stations; it reaches 251 days one year in ten and falls short of 208 one year in ten. On average 71 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 10 days longer, to about April 10, and return around October 31. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 70%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 26 | Apr 1 | Apr 4 | Apr 7 | Apr 10 | Apr 13 | Apr 16 | Apr 19 | Apr 23 |
| 32°F | Mar 12 | Mar 19 | Mar 23 | Mar 27 | Mar 31 | Apr 2 | Apr 4 | Apr 7 | Apr 12 |
| 28°F | Feb 27 | Mar 3 | Mar 8 | Mar 13 | Mar 17 | Mar 20 | Mar 25 | Mar 29 | Apr 2 |
| 24°F | Feb 3 | Feb 12 | Feb 21 | Feb 26 | Mar 1 | Mar 7 | Mar 11 | Mar 16 | Mar 21 |
| 20°F94% of yrs | Jan 13 | Jan 23 | Jan 31 | Feb 5 | Feb 11 | Feb 18 | Feb 25 | Mar 2 | Mar 10 |
| 16°F70% of yrs | Jan 2 | Jan 12 | Jan 18 | Jan 23 | Jan 29 | Jan 31 | Feb 5 | Feb 14 | Feb 27 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 18 | Oct 23 | Oct 26 | Oct 29 | Oct 31 | Nov 2 | Nov 5 | Nov 9 | Nov 13 |
| 32°F | Oct 30 | Nov 1 | Nov 4 | Nov 6 | Nov 10 | Nov 13 | Nov 16 | Nov 21 | Nov 27 |
| 28°F | Nov 7 | Nov 11 | Nov 15 | Nov 19 | Nov 24 | Nov 28 | Dec 1 | Dec 6 | Dec 17 |
| 24°F | Nov 19 | Nov 27 | Dec 1 | Dec 5 | Dec 10 | Dec 17 | Dec 25 | Jan 1 | Jan 10 |
| 20°F94% of yrs | Dec 4 | Dec 13 | Dec 22 | Dec 29 | Jan 2 | Jan 7 | Jan 12 | Jan 18 | Jan 28 |
| 16°F70% of yrs | Dec 19 | Dec 29 | Jan 2 | Jan 7 | Jan 11 | Jan 15 | Jan 22 | Jan 28 | Feb 7 |
Freeze probabilities 1991–2020 at Cary, 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 27539 →Compare Apex with another place →
Weather by month in Apex
July is the warmest month at Cary, NC, averaging 88°F by day and 69°F at night; January is the coldest at 50°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 46% of years.
Warmth for growing adds up to 4,605 growing degree days a year (base 50°F), fewer than at 52% of the 173 North Carolina stations. 38% of them (1,766) have built up by the end of June, and July adds the most, 886.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 50 | 31 | 100% | 20 | 33 |
| Feb | 54 | 33 | 100% | 15 | 45 |
| Mar | 61 | 39 | 96% | 10 | 120 |
| Apr | 71 | 47 | 46% | 1 | 292 |
| May | 78 | 56 | 0% | 0 | 534 |
| Jun | 85 | 65 | 0% | 0 | 742 |
| Jul | 88 | 69 | 0% | 0 | 886 |
| Aug | 86 | 68 | 0% | 0 | 835 |
| Sep | 80 | 62 | 0% | 0 | 627 |
| Oct | 71 | 50 | 15% | <1 | 333 |
| Nov | 62 | 39 | 93% | 8 | 109 |
| Dec | 53 | 34 | 98% | 16 | 48 |
Monthly normals 1991–2020 at Cary, NC (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, Apex, NC, 5 miles northwest of Apex, has a last frost 4 days earlier (March 27), a first frost 2 days earlier (November 8), a season 1 day longer.
When it snows in Apex, North Carolina
Measurable snow is rare here: only 7 of 20 winters from 1991 to 2020 recorded 0.1 inch or more at Raleigh 4 SW, NC, 6.5 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 27539
| 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 18 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 27 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 10 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 27539 is 3 miles from Cary, NC, which stands at 390 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 1 other ZIP code shares the station; its figures are presented in full for 27511 (Cary). The 2023 USDA Plant Hardiness Zone Map lists ZIP 27539 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.