Milan climate

Milan Frost Dates and Growing Season

NOAA 1991-2020 normals for Milan Wwtp, 0.6 km from Milan, elevation 680 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Milan Wwtp. 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 April 26 and the first fall freeze around October 19, a growing season of about 175 days.

Median at 36°F
last May 5, first October 7
Median at 32°F
last April 26, first October 19
Median at 28°F
last April 15, first November 1

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 19May 14May 10May 7May 5May 2Apr 30Apr 27Apr 23
32°FMay 9May 4May 1Apr 29Apr 26Apr 23Apr 20Apr 17Apr 13
28°FApr 30Apr 25Apr 21Apr 18Apr 15Apr 12Apr 9Apr 6Apr 2
24°FApr 19Apr 13Apr 9Apr 6Apr 4Apr 2Mar 30Mar 26Mar 19
20°FApr 7Apr 3Mar 31Mar 29Mar 26Mar 22Mar 19Mar 15Mar 10
16°FMar 31Mar 27Mar 23Mar 19Mar 16Mar 13Mar 10Mar 6Feb 28

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 24Sep 29Oct 2Oct 4Oct 7Oct 10Oct 12Oct 15Oct 20
32°FOct 2Oct 8Oct 12Oct 16Oct 19Oct 22Oct 25Oct 29Nov 3
28°FOct 16Oct 21Oct 25Oct 29Nov 1Nov 2Nov 5Nov 9Nov 14
24°FOct 30Nov 2Nov 5Nov 9Nov 12Nov 15Nov 18Nov 22Nov 28
20°FNov 8Nov 13Nov 17Nov 21Nov 24Nov 28Dec 1Dec 5Dec 12
16°FNov 19Nov 25Nov 30Dec 3Dec 6Dec 10Dec 14Dec 19Dec 24

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°F173167162158155151147141135
32°F197189183179175171167162155
28°F218211207203198195191185178
24°F243236231226221217213208201
20°F266258253248244240235230222
16°F289280274268264260255249241

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
6,431
Cooling degree days, base 65°F
716
Growing degree days, base 40°F
4,988
Growing degree days, base 45°F
3,870
Growing degree days, base 50°F
2,886
Growing degree days, base 55°F
2,033
Growing degree days, base 60°F
1,305

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26101
February1,08501
March921115
April531375
May21739304
June36151566
July4255716
August10192646
September11368408
October4198136
November752017
December1,08202

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 0.6 km from Milan. 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 USC00205451 (Milan Wwtp). Public domain.