USDA Hardiness Zone 7a
Frost Dates for 07823 — Belvidere, New Jersey
NOAA 1991–2020 normals from Belvidere Brg, NJ (263 ft), 2 miles west.
Updated
In Belvidere, the last spring frost (32°F) is around April 30 in half of years and has passed by May 18 in nine years out of ten. The first fall frost comes around October 18, as early as October 3 one year in ten, leaving a typical freeze-free season of 168 days (NOAA, Belvidere Brg, NJ).
- Last spring frost
- April 30
- First fall frost
- October 18
- Growing season
- 168 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 17
- Last snow
- March 9
- Winters with snow
- 97%
- Snow per year
- 23.3"
median, 1991–2020
median, 1991–2020
28 of 29 observed
NOAA normal
Frost risk by date in Belvidere
Half of springs at Belvidere Brg, NJ see their last 32°F night by April 30; only one in ten is past it by April 15, and one in ten still has one after May 18. Planting tender crops after May 7 leaves a 30% risk of a frost on them, after May 11 20%, and after May 18 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 80% of the 56 New Jersey stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 18 in half of years, as early as October 3 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 11 days later, around October 29; in spring the one-in-ten date for 28°F is May 5, 13 days before the 32°F one. The freeze-free season lasts 168 days in a typical year, shorter than at 96% of the 56 New Jersey stations; it reaches 191 days one year in ten and falls short of 145 one year in ten. On average 135 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 May 12, and return around October 6. Severe cold of 16°F or below comes every winter, usually between December 3 and March 10.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 26 | Apr 30 | May 5 | May 9 | May 12 | May 16 | May 20 | May 24 | May 29 |
| 32°F | Apr 15 | Apr 20 | Apr 23 | Apr 26 | Apr 30 | May 3 | May 7 | May 11 | May 18 |
| 28°F | Apr 2 | Apr 6 | Apr 9 | Apr 12 | Apr 16 | Apr 19 | Apr 22 | Apr 26 | May 5 |
| 24°F | Mar 20 | Mar 25 | Mar 30 | Apr 1 | Apr 3 | Apr 5 | Apr 7 | Apr 11 | Apr 16 |
| 20°F | Mar 6 | Mar 12 | Mar 16 | Mar 19 | Mar 22 | Mar 26 | Mar 29 | Mar 31 | Apr 4 |
| 16°F | Feb 22 | Feb 28 | Mar 4 | Mar 7 | Mar 10 | Mar 14 | Mar 17 | Mar 21 | Mar 25 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 25 | Sep 30 | Oct 1 | Oct 4 | Oct 6 | Oct 9 | Oct 12 | Oct 16 | Oct 20 |
| 32°F | Oct 3 | Oct 7 | Oct 11 | Oct 14 | Oct 18 | Oct 20 | Oct 23 | Oct 27 | Nov 1 |
| 28°F | Oct 14 | Oct 19 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 10 |
| 24°F | Oct 26 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 23 |
| 20°F | Nov 5 | Nov 11 | Nov 14 | Nov 17 | Nov 20 | Nov 23 | Nov 27 | Dec 1 | Dec 7 |
| 16°F | Nov 16 | Nov 21 | Nov 27 | Dec 1 | Dec 3 | Dec 7 | Dec 12 | Dec 18 | Dec 26 |
Freeze probabilities 1991–2020 at Belvidere Brg, NJ, 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 07823 →Compare Belvidere with another place →
Weather by month in Belvidere
July is the warmest month at Belvidere Brg, NJ, averaging 84°F by day and 61°F at night; January is the coldest at 37°F and 18°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 45% of years.
Warmth for growing adds up to 2,807 growing degree days a year (base 50°F), fewer than at 93% of the 56 New Jersey stations. 32% of them (884) have built up by the end of June, and July adds the most, 691. Precipitation totals 48.3 inches a year, most in July (4.8") and least in February (2.7"); May to September bring 47% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 37 | 18 | 3.2 | 100% | 28 | 1 |
| Feb | 40 | 19 | 2.7 | 100% | 26 | 0 |
| Mar | 48 | 26 | 3.6 | 100% | 23 | 10 |
| Apr | 61 | 36 | 4.0 | 100% | 9 | 77 |
| May | 71 | 46 | 4.1 | 45% | 1 | 274 |
| Jun | 79 | 56 | 4.5 | 3% | 0 | 522 |
| Jul | 84 | 61 | 4.8 | 0% | 0 | 691 |
| Aug | 83 | 59 | 4.6 | 0% | 0 | 651 |
| Sep | 76 | 52 | 4.6 | 4% | 0 | 425 |
| Oct | 64 | 40 | 4.8 | 87% | 5 | 135 |
| Nov | 52 | 30 | 3.3 | 100% | 18 | 19 |
| Dec | 41 | 24 | 4.1 | 100% | 26 | 2 |
Monthly normals 1991–2020 at Belvidere Brg, NJ (263 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, Phillipsburg-Easton Brg, NJ, 12 miles southwest of Belvidere, has a last frost 12 days earlier (April 18), a first frost 7 days later (October 25), a season 20 days longer.
When it snows in Belvidere, New Jersey
The first measurable snow (0.1 inch or more) in Belvidere usually arrives around December 17, and the last of the season around March 9. Those are the middle dates across the winters of 1991–2020 at Belvidere Brg, NJ, 2 miles away: half of years saw snow earlier, half later. Snow fell in 97% of those winters. The last 32°F night of spring typically comes 52 days after the last snow.
Planting calendar for 07823
| When | What to do |
|---|---|
| February 19 – March 5 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 5 – March 19 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 2 – April 16 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 30 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 26 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 4 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 18 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 07823 is 2 miles from Belvidere Brg, NJ, which stands at 263 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 9 other ZIP codes share the station; its figures are presented in full for 18013 (Bangor). The 2023 USDA Plant Hardiness Zone Map lists ZIP 07823 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.
Frost dates across New Jersey →
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.