USDA Hardiness Zone 6b
Frost Dates for 06247 — Hampton, Connecticut
NOAA 1991–2020 normals from Hampton, CT (490 ft), under a mile east.
Updated
In Hampton, the last spring frost (32°F) is around April 30 in half of years and has passed by May 11 in nine years out of ten. The first fall frost comes around October 15, as early as October 1 one year in ten, leaving a typical freeze-free season of 167 days (NOAA, Hampton, CT).
- Last spring frost
- April 30
- First fall frost
- October 15
- Growing season
- 167 days
- Hardiness zone
- 6b
50% probability
50% probability
freeze-free, 50%
-5 to 0°F (-20.6 to -17.8°C) coldest night
- First snow
- December 5
- Last snow
- March 23
- Winters with snow
- 92%
- Snow per year
- 39"
median, 1991–2020
median, 1991–2020
23 of 25 observed
NOAA normal
Frost risk by date in Hampton
Half of springs at Hampton, CT see their last 32°F night by April 30; only one in ten is past it by April 18, and one in ten still has one after May 11. Planting tender crops after May 4 leaves a 30% risk of a frost on them, after May 7 20%, and after May 11 10%. The 11 days between the even-odds date and the one-in-ten date is the narrowest of the 28 Connecticut stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 15 in half of years, as early as October 1 one year in ten, and holds off past October 29 one year in ten. A hard freeze of 28°F follows 13 days later, around October 28; in spring the one-in-ten date for 28°F is April 30, 11 days before the 32°F one. The freeze-free season lasts 167 days in a typical year, shorter than at 75% of the 28 Connecticut stations; it reaches 187 days one year in ten and falls short of 149 one year in ten. On average 142 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 10 days longer, to about May 10, and return around October 3. Severe cold of 16°F or below comes every winter, usually between December 2 and March 15.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 29 | May 3 | May 5 | May 8 | May 10 | May 12 | May 15 | May 18 | May 23 |
| 32°F | Apr 18 | Apr 21 | Apr 24 | Apr 27 | Apr 30 | May 2 | May 4 | May 7 | May 11 |
| 28°F | Apr 4 | Apr 8 | Apr 11 | Apr 13 | Apr 16 | Apr 19 | Apr 21 | Apr 25 | Apr 30 |
| 24°F | Mar 20 | Mar 27 | Mar 31 | Apr 1 | Apr 3 | Apr 5 | Apr 8 | Apr 11 | Apr 17 |
| 20°F | Mar 9 | Mar 14 | Mar 17 | Mar 20 | Mar 24 | Mar 27 | Mar 31 | Apr 1 | Apr 5 |
| 16°F | Feb 28 | Mar 6 | Mar 9 | Mar 12 | Mar 15 | Mar 17 | Mar 20 | Mar 24 | Mar 29 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 22 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 11 | Oct 16 |
| 32°F | Oct 1 | Oct 5 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 21 | Oct 25 | Oct 29 |
| 28°F | Oct 13 | Oct 17 | Oct 21 | Oct 25 | Oct 28 | Oct 30 | Nov 1 | Nov 4 | Nov 9 |
| 24°F | Oct 25 | Oct 30 | Nov 2 | Nov 5 | Nov 7 | Nov 10 | Nov 14 | Nov 18 | Nov 24 |
| 20°F | Nov 6 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 25 | Nov 28 | Dec 1 | Dec 8 |
| 16°F | Nov 17 | Nov 22 | Nov 27 | Dec 1 | Dec 2 | Dec 5 | Dec 9 | Dec 14 | Dec 22 |
Freeze probabilities 1991–2020 at Hampton, CT, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 06247 →Compare Hampton with another place →
Weather by month in Hampton
July is the warmest month at Hampton, CT, averaging 80°F by day and 60°F at night; January is the coldest at 36°F and 17°F. A freezing night is all but certain in every month from October 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 46% of years.
Warmth for growing adds up to 2,427 growing degree days a year (base 50°F), fewer than at 86% of the 28 Connecticut stations. 30% of them (730) have built up by the end of June, and July adds the most, 626. Precipitation totals 50.6 inches a year, most in December (4.8") and least in February (3.4"); May to September bring 40% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 36 | 17 | 4.1 | 100% | 28 | 0 |
| Feb | 38 | 18 | 3.4 | 100% | 26 | 1 |
| Mar | 46 | 25 | 4.4 | 100% | 25 | 9 |
| Apr | 58 | 35 | 4.7 | 100% | 12 | 52 |
| May | 68 | 45 | 3.7 | 46% | 1 | 220 |
| Jun | 75 | 54 | 4.3 | 0% | 0 | 448 |
| Jul | 80 | 60 | 3.9 | 0% | 0 | 626 |
| Aug | 79 | 58 | 4.2 | 0% | 0 | 572 |
| Sep | 73 | 51 | 4.3 | 7% | 0 | 360 |
| Oct | 62 | 40 | 4.7 | 94% | 6 | 115 |
| Nov | 51 | 31 | 4.1 | 100% | 18 | 22 |
| Dec | 41 | 23 | 4.8 | 100% | 26 | 2 |
Monthly normals 1991–2020 at Hampton, CT (490 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Willimantic Windham Airport, CT, 7 miles west of Hampton and 243 feet lower, has a last frost 2 days earlier (April 28), a first frost 2 days earlier (October 13).
When it snows in Hampton, Connecticut
The first measurable snow (0.1 inch or more) in Hampton usually arrives around December 5, and the last of the season around March 23. Those are the middle dates across the winters of 1991–2020 at Storrs, CT, 8.8 miles away: half of years saw snow earlier, half later. Snow fell in 92% of those winters. The last 32°F night of spring typically comes 38 days after the last snow.
Planting calendar for 06247
| When | What to do |
|---|---|
| February 19 – March 5 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 5 – March 19 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 2 – April 16 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 30 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 23 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 1 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 15 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 06247 is under a mile from Hampton, CT, which stands at 490 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 06234 (Brooklyn). The 2023 USDA Plant Hardiness Zone Map lists ZIP 06247 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Connecticut →
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.