Bradley climate

Bradley Frost Dates and Growing Season

NOAA 1991-2020 normals for Kankakee Metro Wastewater, 2.2 km from Bradley, elevation 600 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Kankakee Metro Wastewater. 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 19 and the first fall freeze around October 24, a growing season of about 188 days.

Median at 36°F
last April 30, first October 14
Median at 32°F
last April 19, first October 24
Median at 28°F
last April 6, first November 4

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 14May 9May 5May 2Apr 30Apr 27Apr 24Apr 20Apr 16
32°FMay 3Apr 28Apr 25Apr 22Apr 19Apr 16Apr 13Apr 10Apr 5
28°FApr 22Apr 17Apr 13Apr 8Apr 6Apr 3Apr 1Mar 28Mar 21
24°FApr 10Apr 5Apr 2Mar 31Mar 27Mar 23Mar 20Mar 16Mar 11
20°FApr 2Mar 29Mar 24Mar 20Mar 17Mar 13Mar 10Mar 6Feb 28
16°FMar 23Mar 18Mar 13Mar 10Mar 7Mar 4Mar 1Feb 26Feb 19

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 1Oct 5Oct 9Oct 12Oct 14Oct 17Oct 20Oct 23Oct 27
32°FOct 12Oct 17Oct 20Oct 22Oct 24Oct 27Oct 29Nov 1Nov 5
28°FOct 23Oct 27Oct 31Nov 1Nov 4Nov 6Nov 11Nov 14Nov 19
24°FNov 1Nov 5Nov 8Nov 11Nov 15Nov 18Nov 21Nov 25Nov 30
20°FNov 8Nov 13Nov 17Nov 21Nov 24Nov 28Dec 1Dec 5Dec 11
16°FNov 16Nov 22Nov 26Nov 30Dec 2Dec 6Dec 10Dec 16Dec 22

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°F184178173170166162158153147
32°F207199195191188183179174167
28°F230223218214211207201196190
24°F255247242237233228224219212
20°F278269263258253249243237229
16°F296288282277272267262256246

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
5,983
Cooling degree days, base 65°F
997
Growing degree days, base 40°F
5,591
Growing degree days, base 45°F
4,417
Growing degree days, base 50°F
3,373
Growing degree days, base 55°F
2,454
Growing degree days, base 60°F
1,660

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,25801
February1,02902
March808231
April4487118
May17272374
June23216643
July2306769
August5256716
September76121497
October35518190
November721131
December1,08602

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 2.2 km from Bradley. 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 USC00114603 (Kankakee Metro Wastewater). Public domain.