Milnor climate

Milnor Frost Dates and Growing Season

NOAA 1991-2020 normals for Mc Leod 3 E, 22.2 km from Milnor, elevation 1075 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mc Leod 3 E. 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 6 and the first fall freeze around September 29, a growing season of about 145 days.

Median at 36°F
last May 16, first September 21
Median at 32°F
last May 6, first September 29
Median at 28°F
last April 29, first October 8

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 28May 24May 21May 18May 16May 13May 11May 7May 3
32°FMay 19May 15May 11May 9May 6May 3May 1Apr 28Apr 24
28°FMay 11May 6May 3May 1Apr 29Apr 25Apr 22Apr 19Apr 14
24°FMay 2Apr 29Apr 25Apr 22Apr 18Apr 16Apr 13Apr 10Apr 5
20°FApr 23Apr 19Apr 15Apr 12Apr 9Apr 7Apr 4Apr 2Mar 29
16°FApr 16Apr 11Apr 8Apr 5Apr 2Apr 1Mar 29Mar 24Mar 17

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 10Sep 14Sep 17Sep 19Sep 21Sep 23Sep 25Sep 28Oct 2
32°FSep 18Sep 22Sep 25Sep 27Sep 29Oct 1Oct 4Oct 6Oct 11
28°FSep 25Sep 30Oct 3Oct 5Oct 8Oct 10Oct 13Oct 17Oct 21
24°FOct 4Oct 9Oct 12Oct 15Oct 18Oct 20Oct 23Oct 27Nov 1
20°FOct 12Oct 18Oct 22Oct 25Oct 28Oct 31Nov 2Nov 5Nov 10
16°FOct 23Oct 29Nov 1Nov 3Nov 5Nov 8Nov 11Nov 15Nov 20

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°F145139135131128125121116110
32°F162156152149145142138133127
28°F181175170166161158155150144
24°F202194190186182178174169162
20°F219212208204199196192188181
16°F237230225220216213209204196

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
8,811
Cooling degree days, base 65°F
557
Growing degree days, base 40°F
4,260
Growing degree days, base 45°F
3,297
Growing degree days, base 50°F
2,440
Growing degree days, base 55°F
1,690
Growing degree days, base 60°F
1,059

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,74000
February1,44300
March1,17304
April662142
May28627250
June60116506
July15204654
August31161595
September19246320
October612367
November1,06502
December1,53100

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 22.2 km from Milnor. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

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Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00325754 (Mc Leod 3 E). Public domain.