Frost dates 2026–2027

Frost dates for Mount Arlington, New Jersey

Median (50% chance) dates of the last and first 32°F frost, from NOAA 1991–2020 climate normals at Andover Aeroflex Airport, 7.9 mi away (close match).

Last spring frostApr 25
First fall frostOct 19
175 frost-free days
Last spring frostApr 251 year in 10 after May 11
First fall frostOct 191 year in 10 by Oct 5
Growing season175 daysbetween median 32°F dates
Hardiness zoneZone 6b−5 to 0°F average extreme low

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Will it freeze in Mount Arlington in the next 7 nights?

No overnight lows at or below 32°F are forecast in Mount Arlington during the next 7 nights in the available NWS frost forecast.

Tonight: forecast low 59°F. Above 36°F.

NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.

2 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.

Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.

Frost and freeze probabilities

Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.

These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.

Average first hard freeze in Mount Arlington

The median first fall hard-freeze date (28°F) is October 31, from NOAA’s 1991–2020 Climate Normals at Andover Aeroflex Airport. This is the 50% probability date, not a forecast for this year.

TemperatureLast spring date
90% · 50% · 10% chance of a later freeze
First fall date
10% · 50% · 90% chance of an earlier freeze
Season
36°F frost possible Apr 22 · May 7 · May 22 Sep 26 · Oct 6 · Oct 22 152 days
32°F freeze Apr 12 · Apr 25 · May 11 Oct 5 · Oct 19 · Nov 3 175 days
28°F hard freeze Mar 31 · Apr 11 · Apr 28 Oct 15 · Oct 31 · Nov 13 202 days
NOAA NCEI U.S. Climate Normals 1991–2020, station USW00054779. How to read these probabilities.

Average high temperature by month

1991–2020 normals at Andover Aeroflex Airport

Average low temperature by month

Months with lows near or below freezing carry frost risk

Where these frost dates come from

The frost dates for Mount Arlington, NJ come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Andover Aeroflex Airport (station USW00054779, elevation 583 ft), 7.9 mi from Mount Arlington. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.

Frost dates near Mount Arlington

CityDistanceLast spring frostFirst fall frost
Hopatcong, NJ 2.5 mi Apr 25 Oct 19
Wharton, NJ 3.7 mi Apr 17 Oct 23
Dover, NJ 5.0 mi Apr 17 Oct 23
Rockaway, NJ 6.8 mi Apr 17 Oct 23
Morris Plains, NJ 11 mi Apr 17 Oct 23
Hackettstown, NJ 11 mi Apr 25 Oct 19
Newton, NJ 11 mi Apr 24 Oct 16
Morristown, NJ 12 mi Apr 18 Oct 27
Boonton, NJ 12 mi Apr 17 Oct 23
Franklin, NJ 13 mi May 1 Oct 12

Frequently asked questions

When is the last frost in Mount Arlington?

On average, the last spring frost (32°F) in Mount Arlington is around April 25. In about 1 year in 10 it comes after May 11, and in 9 years in 10 it comes after April 12.

When is the first frost in Mount Arlington?

The first fall frost (32°F) usually arrives around October 19. There’s a 10% chance of a freeze by October 5 and a 90% chance by November 3.

Can it frost in Mount Arlington after the last frost date?

Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 7.

What growing zone is Mount Arlington?

Mount Arlington is in USDA Plant Hardiness Zone 6b (average annual extreme minimum temperature −5 to 0°F), based on the 2023 USDA map for ZIP code 07856. See growing zones in New Jersey.

More: all New Jersey frost dates · New Jersey growing zones · frost vs. freeze