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USDA Hardiness Zone 5a

Frost Dates for 04461 — Milford, Maine

NOAA 1991–2020 normals from Old Town 2 W, ME (127 ft), 4 miles southwest.

Updated

In Milford, the last spring frost (32°F) is around May 13 in half of years and has passed by May 28 in nine years out of ten. The first fall frost comes around September 28, as early as September 16 one year in ten, leaving a typical freeze-free season of 137 days (NOAA, Old Town 2 W, ME).

Last spring frost
May 13

50% probability

First fall frost
September 28

50% probability

Growing season
137 days

freeze-free, 50%

Hardiness zone
5a

-20 to -15°F (-28.9 to -26.1°C) coldest night

First snow
November 24

median, 1991–2020

Last snow
April 6

median, 1991–2020

Winters with snow
100%

29 of 29 observed

Snow per year
74.6"

NOAA normal

Frost risk by date in Milford

Half of springs at Old Town 2 W, ME see their last 32°F night by May 13; only one in ten is past it by April 30, and one in ten still has one after May 28. Planting tender crops after May 19 leaves a 30% risk of a frost on them, after May 23 20%, and after May 28 10%. The 15 days between the even-odds date and the one-in-ten date is wider than at 83% of the 52 Maine stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 28 in half of years, as early as September 16 one year in ten, and holds off past October 11 one year in ten. A hard freeze of 28°F follows 13 days later, around October 11; in spring the one-in-ten date for 28°F is May 13, 15 days before the 32°F one. The freeze-free season lasts 137 days in a typical year, shorter than at 81% of the 52 Maine stations; it reaches 155 days one year in ten and falls short of 117 one year in ten. On average 173 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 15 days longer, to about May 28, and return around September 18. Severe cold of 16°F or below comes every winter, usually between November 20 and March 31.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FMay 14May 18May 22May 25May 28May 31Jun 2Jun 5Jun 9
32°FApr 30May 3May 7May 11May 13May 16May 19May 23May 28
28°FApr 19Apr 22Apr 25Apr 28Apr 30May 2May 4May 8May 13
24°FApr 4Apr 8Apr 12Apr 15Apr 18Apr 21Apr 23Apr 26Apr 29
20°FMar 26Mar 31Apr 2Apr 4Apr 6Apr 8Apr 12Apr 15Apr 20
16°FMar 16Mar 20Mar 24Mar 28Mar 31Apr 1Apr 3Apr 6Apr 10
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FSep 5Sep 9Sep 12Sep 15Sep 18Sep 21Sep 24Sep 27Oct 1
32°FSep 16Sep 21Sep 24Sep 26Sep 28Oct 1Oct 4Oct 7Oct 11
28°FSep 27Oct 1Oct 5Oct 8Oct 11Oct 14Oct 17Oct 22Oct 28
24°FOct 9Oct 15Oct 19Oct 24Oct 27Oct 30Nov 2Nov 5Nov 10
20°FOct 26Nov 1Nov 3Nov 6Nov 9Nov 11Nov 14Nov 18Nov 22
16°FNov 6Nov 11Nov 14Nov 17Nov 20Nov 22Nov 25Nov 28Dec 3

Freeze probabilities 1991–2020 at Old Town 2 W, 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 04461 →Compare Milford with another place →

Weather by month in Milford

July is the warmest month at Old Town 2 W, ME, averaging 79°F by day and 56°F at night; January is the coldest at 27°F and 6°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 87% of years.

Warmth for growing adds up to 1,816 growing degree days a year (base 50°F), fewer than at 83% of the 52 Maine stations. 27% of them (486) have built up by the end of June, and July adds the most, 542. Precipitation totals 44.8 inches a year, most in October (4.3") and least in February (3.0"); May to September bring 40% of it.

Monthly normals 1991–2020 at Old Town 2 W, ME
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan2763.7100%300
Feb3183.0100%270
Mar39193.8100%292
Apr52303.7100%1915
May65413.587%4128
Jun73504.26%<1341
Jul79563.50%0542
Aug78533.20%0482
Sep70463.757%2249
Oct57364.3100%1151
Nov44274.0100%236
Dec34164.2100%290

Monthly normals 1991–2020 at Old Town 2 W, ME (127 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, Orono, ME, 5 miles southwest of Milford, has a last frost 12 days earlier (May 1), a first frost 8 days later (October 6), a season 20 days longer.

Frost dates for 04473 (Orono) →

When it snows in Milford, Maine

The first measurable snow (0.1 inch or more) in Milford usually arrives around November 24, and the last of the season around April 6. Those are the middle dates across the winters of 1991–2020 at Bangor International Airport, ME, 14.6 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 04461

What to do and when, from the 50% frost dates for Milford, Maine
WhenWhat to do
March 4 – March 18Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 18 – April 1Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 15 – April 29Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 13 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 6Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 14Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
September 28 onwardPlant 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 04461 is 4 miles from Old Town 2 W, ME, which stands at 127 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 04468 (Old Town). The 2023 USDA Plant Hardiness Zone Map lists ZIP 04461 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Maine →

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.

ZIP codes measured at the same station

Other zone 5a places in Maine