Frost dates 2026–2027

Frost dates for New London, Connecticut

Median (50% chance) dates of the last and first 32°F frost, from NOAA 1991–2020 climate normals at Groton New London Airport, 2.5 mi away (close match).

Last spring frostApr 16
First fall frostOct 28
194 frost-free days
Last spring frostApr 161 year in 10 after Apr 30
First fall frostOct 281 year in 10 by Oct 13
Growing season194 daysbetween median 32°F dates
Hardiness zoneZone 7a0 to 5°F average extreme low

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Will it freeze in New London in the next 7 nights?

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

Tonight: forecast low 63°F. Above 36°F.

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

1 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 New London

The median first fall hard-freeze date (28°F) is November 9, from NOAA’s 1991–2020 Climate Normals at Groton New London 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 18 · Apr 29 · May 11 Oct 5 · Oct 16 · Oct 31 170 days
32°F freeze Apr 3 · Apr 16 · Apr 30 Oct 13 · Oct 28 · Nov 12 194 days
28°F hard freeze Mar 19 · Apr 3 · Apr 17 Oct 25 · Nov 9 · Nov 27 220 days
NOAA NCEI U.S. Climate Normals 1991–2020, station USW00014707. How to read these probabilities.

Average high temperature by month

1991–2020 normals at Groton New London 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 New London, CT come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Groton New London Airport (station USW00014707, elevation 10 ft), 2.5 mi from New London. 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 New London

CityDistanceLast spring frostFirst fall frost
Groton, CT 1.9 mi Apr 16 Oct 28
Norwich, CT 15 mi Apr 14 Oct 24
Middletown, CT 33 mi Apr 26 Oct 16
Meriden, CT 39 mi Apr 26 Oct 16
Newport, RI 42 mi Apr 7 Nov 13
Hartford, CT 42 mi Apr 17 Oct 26
New Britain, CT 43 mi Apr 17 Oct 26
New Haven, CT 43 mi Apr 17 Oct 27
Warwick, RI 43 mi Apr 11 Oct 30
Cranston, RI 43 mi Apr 11 Oct 30

Frequently asked questions

When is the last frost in New London?

On average, the last spring frost (32°F) in New London is around April 16. In about 1 year in 10 it comes after April 30, and in 9 years in 10 it comes after April 3.

When is the first frost in New London?

The first fall frost (32°F) usually arrives around October 28. There’s a 10% chance of a freeze by October 13 and a 90% chance by November 12.

Can it frost in New London 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 April 29.

What growing zone is New London?

New London is in USDA Plant Hardiness Zone 7a (average annual extreme minimum temperature 0 to 5°F), based on the 2023 USDA map for ZIP code 06320. See growing zones in Connecticut.

More: all Connecticut frost dates · Connecticut growing zones · UV index today in New London · frost vs. freeze