Milford climate

Milford Frost Dates and Growing Season

NOAA 1991-2020 normals for Milford 4 Nw, 7 km from Milford, elevation 1402 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Milford 4 Nw. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around May 1 and the first fall freeze around October 6, a growing season of about 158 days.

Median at 36°F
last May 9, first September 28
Median at 32°F
last May 1, first October 6
Median at 28°F
last April 21, first October 17

Last freeze in spring

The chance of a later freeze than the date shown. At 10 percent, one spring in ten still freezes after the date; planting after the 10 percent date for 32°F is the cautious choice.

Threshold10%20%30%40%50%60%70%80%90%
36°FMay 22May 18May 15May 11May 9May 7May 4May 2Apr 28
32°FMay 14May 9May 5May 3May 1Apr 28Apr 25Apr 22Apr 17
28°FMay 4Apr 30Apr 27Apr 23Apr 21Apr 18Apr 15Apr 11Apr 6
24°FApr 27Apr 21Apr 17Apr 14Apr 11Apr 7Apr 4Apr 2Mar 29
20°FApr 19Apr 13Apr 9Apr 6Apr 3Apr 1Mar 29Mar 24Mar 17
16°FApr 12Apr 6Apr 2Mar 30Mar 27Mar 23Mar 18Mar 14Mar 10

First freeze in fall

The chance of an earlier freeze than the date shown. At 10 percent, one fall in ten freezes before the date.

Threshold10%20%30%40%50%60%70%80%90%
36°FSep 15Sep 19Sep 23Sep 26Sep 28Oct 1Oct 3Oct 6Oct 11
32°FSep 24Sep 29Oct 1Oct 4Oct 6Oct 9Oct 13Oct 17Oct 21
28°FOct 2Oct 6Oct 11Oct 14Oct 17Oct 20Oct 23Oct 26Oct 29
24°FOct 13Oct 19Oct 22Oct 25Oct 28Oct 30Nov 1Nov 4Nov 9
20°FOct 23Oct 28Oct 31Nov 1Nov 4Nov 6Nov 9Nov 12Nov 17
16°FOct 30Nov 2Nov 6Nov 8Nov 11Nov 14Nov 16Nov 21Nov 25

Growing season length

Days between the last spring and first fall freeze at each threshold, with the chance of a season at least that long.

Threshold10%20%30%40%50%60%70%80%90%
36°F158152148145141138134129123
32°F177171166162158155151146140
28°F198191186182178174170165158
24°F219212206202198194189184178
20°F236228223218214210206200193
16°F251243237232227223219215206

How often it gets that cold

The share of years with at least one night at or below each temperature.

36°F or colder
100% of years
32°F or colder
100% of years
28°F or colder
100% of years
24°F or colder
100% of years
20°F or colder
100% of years
16°F or colder
100% of years

Degree days

A degree day is one degree of the daily mean temperature beyond a base, for one day. Heating degree days count cold (the fuel a house burns), cooling degree days heat, growing degree days the warmth a crop needs; each crop has its own base.

Heating degree days, base 65°F
7,569
Cooling degree days, base 65°F
684
Growing degree days, base 40°F
4,751
Growing degree days, base 45°F
3,711
Growing degree days, base 50°F
2,777
Growing degree days, base 55°F
1,956
Growing degree days, base 60°F
1,252

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,52000
February1,25300
March1,000012
April568473
May23738291
June37150563
July7240697
August19174620
September13671393
October4956117
November936011
December1,36100

What this means

NOAA computes these from the daily lows at the station over 1991-2020, fitting the dates of each year's last and first freeze to a distribution, so a date can be stated at any level of risk. 36°F is a frost risk for tender plants on a clear, calm night, since the ground cools below the air above it; 32°F is a freeze; 28°F is a hard freeze that kills most annuals.

The station is 7 km from Milford. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00135493 (Milford 4 Nw). Public domain.