Benld climate

Benld Frost Dates and Growing Season

NOAA 1991-2020 normals for Carlinville, 22.5 km from Benld, elevation 621 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Carlinville. 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 14 and the first fall freeze around October 21, a growing season of about 188 days.

Median at 36°F
last April 25, first October 11
Median at 32°F
last April 14, first October 21
Median at 28°F
last April 2, 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 12May 6May 2Apr 29Apr 25Apr 22Apr 19Apr 16Apr 10
32°FApr 30Apr 24Apr 20Apr 17Apr 14Apr 10Apr 7Apr 3Mar 31
28°FApr 17Apr 11Apr 7Apr 4Apr 2Mar 30Mar 27Mar 23Mar 17
24°FApr 7Apr 2Mar 30Mar 26Mar 22Mar 18Mar 15Mar 10Mar 3
20°FMar 31Mar 23Mar 19Mar 15Mar 12Mar 8Mar 5Mar 1Feb 23
16°FMar 20Mar 14Mar 11Mar 7Mar 4Mar 1Feb 25Feb 20Feb 11

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 25Sep 30Oct 4Oct 8Oct 11Oct 13Oct 16Oct 19Oct 23
32°FOct 5Oct 11Oct 15Oct 19Oct 21Oct 24Oct 26Oct 29Nov 1
28°FOct 18Oct 23Oct 27Oct 30Nov 1Nov 2Nov 5Nov 9Nov 15
24°FOct 30Nov 2Nov 5Nov 8Nov 11Nov 14Nov 18Nov 24Nov 30
20°FNov 6Nov 12Nov 15Nov 19Nov 23Nov 27Dec 1Dec 5Dec 11
16°FNov 15Nov 21Nov 26Nov 30Dec 3Dec 7Dec 11Dec 17Dec 23

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°F186180175170166162157153144
32°F209202197193188184179174167
28°F233226221216212208204199192
24°F258250244239234230225219212
20°F279271264259254249244239231
16°F299290283278273268263258249

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
5,320
Cooling degree days, base 65°F
1,142
Growing degree days, base 40°F
6,098
Growing degree days, base 45°F
4,844
Growing degree days, base 50°F
3,725
Growing degree days, base 55°F
2,733
Growing degree days, base 60°F
1,867

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,15703
February92007
March711359
April34616189
May12487432
June14246682
July2346809
August5293753
September66130516
October31822219
November659150
December1,00008

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 22.5 km from Benld. 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 USC00111280 (Carlinville). Public domain.