USDA Hardiness Zone 5b
Frost Dates for 04974 — Searsport, Maine
NOAA 1991–2020 normals from Belfast, ME (20 ft), 8 miles south.
Updated
In Searsport, the last spring frost (32°F) is around May 7 in half of years and has passed by May 21 in nine years out of ten. The first fall frost comes around October 5, as early as September 24 one year in ten, leaving a typical freeze-free season of 151 days (NOAA, Belfast, ME).
- Last spring frost
- May 7
- First fall frost
- October 5
- Growing season
- 151 days
- Hardiness zone
- 5b
50% probability
50% probability
freeze-free, 50%
-15 to -10°F (-26.1 to -23.3°C) coldest night
- First snow
- December 2
- Last snow
- March 31
- Winters with snow
- 100%
- Snow per year
- 71.5"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Searsport
Half of springs at Belfast, ME see their last 32°F night by May 7; only one in ten is past it by April 28, and one in ten still has one after May 21. Planting tender crops after May 13 leaves a 30% risk of a frost on them, after May 16 20%, and after May 21 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 69% of the 52 Maine stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 5 in half of years, as early as September 24 one year in ten, and holds off past October 20 one year in ten. A hard freeze of 28°F follows 14 days later, around October 19; in spring the one-in-ten date for 28°F is May 6, 15 days before the 32°F one. The freeze-free season lasts 151 days in a typical year, shorter than at 48% of the 52 Maine stations; it reaches 167 days one year in ten and falls short of 133 one year in ten. On average 162 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 14 days longer, to about May 21, and return around September 27. Severe cold of 16°F or below comes every winter, usually between November 25 and March 25.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 9 | May 12 | May 15 | May 18 | May 21 | May 23 | May 26 | May 28 | Jun 1 |
| 32°F | Apr 28 | Apr 30 | May 3 | May 5 | May 7 | May 10 | May 13 | May 16 | May 21 |
| 28°F | Apr 13 | Apr 19 | Apr 22 | Apr 25 | Apr 27 | Apr 29 | May 1 | May 3 | May 6 |
| 24°F | Apr 1 | Apr 5 | Apr 7 | Apr 10 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 26 |
| 20°F | Mar 20 | Mar 26 | Mar 30 | Apr 1 | Apr 3 | Apr 4 | Apr 7 | Apr 9 | Apr 15 |
| 16°F | Mar 12 | Mar 15 | Mar 18 | Mar 21 | Mar 25 | Mar 29 | Mar 31 | Apr 2 | Apr 5 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 15 | Sep 19 | Sep 22 | Sep 25 | Sep 27 | Sep 29 | Oct 1 | Oct 4 | Oct 8 |
| 32°F | Sep 24 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 11 | Oct 15 | Oct 20 |
| 28°F | Oct 3 | Oct 8 | Oct 12 | Oct 15 | Oct 19 | Oct 22 | Oct 26 | Oct 31 | Nov 3 |
| 24°F | Oct 17 | Oct 23 | Oct 27 | Oct 31 | Nov 2 | Nov 5 | Nov 7 | Nov 12 | Nov 16 |
| 20°F | Nov 1 | Nov 4 | Nov 9 | Nov 12 | Nov 14 | Nov 18 | Nov 21 | Nov 24 | Nov 29 |
| 16°F | Nov 11 | Nov 16 | Nov 20 | Nov 23 | Nov 25 | Nov 28 | Dec 1 | Dec 3 | Dec 8 |
Freeze probabilities 1991–2020 at Belfast, ME, 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 04974 →Compare Searsport with another place →
Weather by month in Searsport
July is the warmest month at Belfast, ME, averaging 77°F by day and 57°F at night; January is the coldest at 30°F and 10°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 80% of years.
Warmth for growing adds up to 1,802 growing degree days a year (base 50°F), fewer than at 87% of the 52 Maine stations. 25% of them (456) have built up by the end of June, and July adds the most, 521. Precipitation totals 49.0 inches a year, most in October (5.4") and least in August (3.1"); May to September bring 38% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 30 | 10 | 3.9 | 100% | 30 | 0 |
| Feb | 32 | 12 | 3.2 | 100% | 27 | 0 |
| Mar | 40 | 20 | 4.1 | 100% | 28 | 1 |
| Apr | 52 | 31 | 4.4 | 100% | 17 | 11 |
| May | 63 | 41 | 3.9 | 80% | 2 | 113 |
| Jun | 72 | 51 | 4.3 | 0% | 0 | 332 |
| Jul | 77 | 57 | 3.2 | 0% | 0 | 521 |
| Aug | 76 | 56 | 3.1 | 0% | 0 | 494 |
| Sep | 70 | 48 | 4.1 | 25% | 1 | 271 |
| Oct | 57 | 38 | 5.4 | 98% | 8 | 54 |
| Nov | 46 | 29 | 4.7 | 100% | 20 | 5 |
| Dec | 35 | 18 | 4.7 | 100% | 29 | 0 |
Monthly normals 1991–2020 at Belfast, ME (20 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, Bangor International Airport, ME, 21 miles north of Searsport, has a last frost 3 days earlier (May 4), a first frost 1 day earlier (October 4), a season 1 day longer.
When it snows in Searsport, Maine
The first measurable snow (0.1 inch or more) in Searsport usually arrives around December 2, and the last of the season around March 31. Those are the middle dates across the winters of 1991–2020 at Belfast, ME, 7.9 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 37 days after the last snow.
Planting calendar for 04974
| When | What to do |
|---|---|
| February 26 – March 12 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 12 – March 26 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 9 – April 23 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 7 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 13 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 21 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 5 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 04974 is 8 miles from Belfast, ME, which stands at 20 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 04915 (Belfast). The 2023 USDA Plant Hardiness Zone Map lists ZIP 04974 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.
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.