Frost Dates for 07068 — Roseland, New Jersey

Half of springs at Essex Fells Service Bldg, NJ see their last 32°F night by April 18; only one in ten is past it by April 3, and one in ten still has one after May 7. Planting tender crops after April 25 leaves a 30% risk of a frost on them, after April 30 20%, and after May 7 10%. The 19 days between the even-odds date and the one-in-ten date is wider than at 91% of the 56 New Jersey stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 24 in half of years, as early as October 8 one year in ten, and holds off past November 6 one year in ten. A hard freeze of 28°F follows 11 days later, around November 4; in spring the one-in-ten date for 28°F is April 19, 18 days before the 32°F one. The freeze-free season lasts 187 days in a typical year, shorter than at 68% of the 56 New Jersey stations; it reaches 207 days one year in ten and falls short of 164 one year in ten. On average 118 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 May 1, and return around October 11. Severe cold of 16°F or below comes every winter, usually between December 19 and March 4.

July is the warmest month at Essex Fells Service Bldg, NJ, averaging 86°F by day and 64°F at night; January is the coldest at 38°F and 21°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 20% of years.

Warmth for growing adds up to 3,247 growing degree days a year (base 50°F), fewer than at 71% of the 56 New Jersey stations. 33% of them (1,064) have built up by the end of June, and July adds the most, 772.

The nearest other station, Caldwell Essex Co Airport, NJ, 4 miles north of Roseland and 177 feet lower, has a last frost 4 days earlier (April 14), a first frost 4 days later (October 28), a season 9 days longer.

The first measurable snow (0.1 inch or more) in Roseland usually arrives around December 20, and the last of the season around March 18. Those are the middle dates across the winters of 1991–2020 at Canoe Brook, NJ, 6 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 31 days after the last snow.

ZIP 07068 is 1 mile from Essex Fells Service Bldg, NJ, which stands at 350 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 8 other ZIP codes share the station; its figures are presented in full for 07052 (West Orange). The 2023 USDA Plant Hardiness Zone Map lists ZIP 07068 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.