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Frost Dates for Lake Chaffee, CT

Last spring frost
Apr 19
First fall frost
Oct 22
Growing season
186 days
Hardiness zone
6b

In an average year around Lake Chaffee, CT, the last spring frost (32°F) is about Apr 19 and the first fall frost is about Oct 22, giving roughly a 186-day growing season. To be safe most years, wait until Apr 7 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Lake Chaffee, CT
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 16 May 3 Apr 20
Freeze (32°F) May 3 Apr 19 Apr 7
Hard (28°F) Apr 19 Apr 6 Mar 26
Severe (24°F) Apr 8 Mar 30 Mar 15
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 16 May 11 May 8 May 5 May 3 Apr 30 Apr 28 Apr 24 Apr 20
32°F May 3 Apr 29 Apr 25 Apr 22 Apr 19 Apr 17 Apr 14 Apr 11 Apr 7
28°F Apr 19 Apr 14 Apr 11 Apr 8 Apr 6 Apr 4 Apr 2 Mar 31 Mar 26
24°F Apr 8 Apr 4 Apr 3 Apr 1 Mar 30 Mar 27 Mar 23 Mar 20 Mar 15
20°F Apr 1 Mar 30 Mar 25 Mar 22 Mar 19 Mar 16 Mar 13 Mar 9 Mar 5
16°F Mar 26 Mar 21 Mar 17 Mar 14 Mar 11 Mar 8 Mar 5 Mar 2 Feb 24

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Lake Chaffee, CT
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 29 Oct 10 Oct 25
Freeze (32°F) Oct 6 Oct 22 Nov 6
Hard (28°F) Oct 19 Nov 4 Nov 20
Severe (24°F) Nov 2 Nov 18 Dec 4
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 29 Oct 2 Oct 5 Oct 7 Oct 10 Oct 13 Oct 16 Oct 20 Oct 25
32°F Oct 6 Oct 11 Oct 15 Oct 19 Oct 22 Oct 25 Oct 29 Nov 1 Nov 6
28°F Oct 19 Oct 26 Oct 30 Nov 1 Nov 4 Nov 7 Nov 11 Nov 14 Nov 20
24°F Nov 2 Nov 8 Nov 11 Nov 14 Nov 18 Nov 21 Nov 25 Nov 30 Dec 4
20°F Nov 13 Nov 18 Nov 23 Nov 27 Nov 30 Dec 2 Dec 6 Dec 10 Dec 17
16°F Nov 24 Nov 30 Dec 2 Dec 6 Dec 9 Dec 14 Dec 18 Dec 23 Dec 30

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Storrs, Ct, about 7.6 miles away@if(!empty($station['elevation_ft'])), at 665 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

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How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Lake Chaffee, CT?

On average, the last spring frost (32°F) around Lake Chaffee, CT is about Apr 19. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 7.

When is the first frost in the fall?

The first fall frost around Lake Chaffee, CT typically arrives about Oct 22. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 19 on average, or Apr 7 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 186 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 06278 Planting calendar → Connecticut frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026