Menard County climate

Menard County Frost Dates and Growing Season

NOAA 1991-2020 normals for Menard, 3.6 km from Menard County, elevation 1979 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Menard. 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 7 and the first fall freeze around October 30, a growing season of about 204 days.

Median at 36°F
last April 18, first October 21
Median at 32°F
last April 7, first October 30
Median at 28°F
last March 27, first November 5

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°FApr 30Apr 27Apr 24Apr 21Apr 18Apr 15Apr 12Apr 8Apr 3
32°FApr 23Apr 18Apr 14Apr 10Apr 7Apr 4Apr 1Mar 28Mar 20
28°FApr 14Apr 7Apr 4Apr 1Mar 27Mar 22Mar 18Mar 13Mar 6
24°FApr 2Mar 24Mar 19Mar 15Mar 11Mar 8Mar 3Feb 27Feb 20
20°FMar 17Mar 11Mar 7Mar 2Feb 28Feb 22Feb 17Feb 11Feb 1
16°FMar 8Mar 1Feb 21Feb 14Feb 7Feb 1Jan 26Jan 17Jan 2

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°FOct 6Oct 10Oct 15Oct 18Oct 21Oct 24Oct 27Oct 31Nov 4
32°FOct 15Oct 20Oct 24Oct 27Oct 30Nov 1Nov 4Nov 7Nov 12
28°FOct 24Oct 29Nov 1Nov 3Nov 5Nov 9Nov 12Nov 17Nov 24
24°FOct 31Nov 5Nov 8Nov 13Nov 18Nov 22Nov 26Dec 1Dec 7
20°FNov 8Nov 16Nov 22Nov 26Nov 30Dec 3Dec 8Dec 15Dec 24
16°FNov 21Nov 29Dec 4Dec 9Dec 17Dec 25Jan 1Jan 7Jan 21

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°F207199193188185181176172165
32°F228219213208204199195190183
28°F255244236231224220215209202
24°F278269262255249245238232222
20°F313300290284276270265257246
16°F352340329322313304297288274

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
96% 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
2,581
Cooling degree days, base 65°F
2,137
Growing degree days, base 40°F
8,836
Growing degree days, base 45°F
7,202
Growing degree days, base 50°F
5,699
Growing degree days, base 55°F
4,343
Growing degree days, base 60°F
3,156

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January631150
February455392
March29718236
April11285431
May21238682
June1402852
July0510975
August0493958
September10283723
October10992455
November35311180
December591165

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 3.6 km from Menard County. 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 USC00415822 (Menard). Public domain.