Harman US

Frost Dates for Westford, VT

Last spring frost
May 2
First fall frost
Oct 11
Growing season
160 days
Hardiness zone
5a

In an average year around Westford, VT, the last spring frost (32°F) is about May 2 and the first fall frost is about Oct 11, giving roughly a 160-day growing season. To be safe most years, wait until Apr 21 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 - Westford, VT
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 30 May 16 May 1
Freeze (32°F) May 17 May 2 Apr 21
Hard (28°F) May 5 Apr 23 Apr 9
Severe (24°F) Apr 23 Apr 11 Mar 31
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 30 May 25 May 21 May 18 May 16 May 12 May 8 May 5 May 1
32°F May 17 May 12 May 8 May 5 May 2 Apr 30 Apr 28 Apr 25 Apr 21
28°F May 5 Apr 30 Apr 27 Apr 25 Apr 23 Apr 20 Apr 17 Apr 14 Apr 9
24°F Apr 23 Apr 20 Apr 16 Apr 14 Apr 11 Apr 9 Apr 6 Apr 3 Mar 31
20°F Apr 15 Apr 11 Apr 7 Apr 5 Apr 3 Apr 1 Mar 31 Mar 27 Mar 21
16°F Apr 7 Apr 4 Apr 2 Mar 31 Mar 29 Mar 25 Mar 22 Mar 19 Mar 14

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 - Westford, VT
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 19 Oct 1 Oct 13
Freeze (32°F) Sep 30 Oct 11 Oct 26
Hard (28°F) Oct 8 Oct 24 Nov 7
Severe (24°F) Oct 21 Nov 5 Nov 19
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 19 Sep 23 Sep 27 Sep 29 Oct 1 Oct 3 Oct 5 Oct 9 Oct 13
32°F Sep 30 Oct 3 Oct 5 Oct 8 Oct 11 Oct 14 Oct 17 Oct 21 Oct 26
28°F Oct 8 Oct 14 Oct 18 Oct 21 Oct 24 Oct 27 Oct 30 Nov 2 Nov 7
24°F Oct 21 Oct 27 Oct 31 Nov 3 Nov 5 Nov 8 Nov 12 Nov 15 Nov 19
20°F Nov 4 Nov 7 Nov 11 Nov 14 Nov 16 Nov 19 Nov 22 Nov 25 Nov 30
16°F Nov 11 Nov 15 Nov 19 Nov 22 Nov 25 Nov 28 Dec 1 Dec 4 Dec 9

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: Essex Junction 1 N, Vt, about 8.2 miles away@if(!empty($station['elevation_ft'])), at 340 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
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 Westford, VT?

On average, the last spring frost (32°F) around Westford, VT is about May 2. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 21.

When is the first frost in the fall?

The first fall frost around Westford, VT typically arrives about Oct 11. 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 May 2 on average, or Apr 21 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 160 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 05494 Planting calendar → Vermont frost dates →

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