Buffalo Grove climate

Buffalo Grove Frost Dates and Growing Season

NOAA 1991-2020 normals for Chicago Palwaukee AP, 5.7 km from Buffalo Grove, elevation 636 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Chicago Palwaukee AP. 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 26, a growing season of about 190 days.

Median at 36°F
last April 30, first October 16
Median at 32°F
last April 19, first October 26
Median at 28°F
last April 5, first November 7

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 15May 10May 6May 3Apr 30Apr 28Apr 24Apr 21Apr 16
32°FMay 3Apr 28Apr 25Apr 22Apr 19Apr 16Apr 13Apr 9Apr 4
28°FApr 20Apr 16Apr 11Apr 8Apr 5Apr 3Mar 31Mar 28Mar 22
24°FApr 7Apr 3Mar 31Mar 29Mar 25Mar 22Mar 18Mar 14Mar 9
20°FMar 30Mar 24Mar 20Mar 17Mar 14Mar 11Mar 9Mar 5Feb 28
16°FMar 20Mar 15Mar 12Mar 9Mar 6Mar 3Feb 28Feb 24Feb 15

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 6Oct 10Oct 13Oct 16Oct 18Oct 21Oct 24Oct 27
32°FOct 13Oct 18Oct 22Oct 24Oct 26Oct 29Oct 31Nov 4Nov 9
28°FOct 26Oct 30Nov 1Nov 4Nov 7Nov 9Nov 12Nov 15Nov 21
24°FNov 4Nov 8Nov 11Nov 14Nov 17Nov 20Nov 23Nov 27Dec 2
20°FNov 11Nov 16Nov 20Nov 24Nov 27Nov 29Dec 2Dec 6Dec 13
16°FNov 19Nov 25Nov 29Dec 1Dec 5Dec 8Dec 12Dec 17Dec 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°F186179175171167164159155148
32°F207201197193190186183177170
28°F234226220217212209205201194
24°F258250245241237232228223217
20°F278270264260256252248242236
16°F296289283278273270265260252

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
6,085
Cooling degree days, base 65°F
933
Growing degree days, base 40°F
5,388
Growing degree days, base 45°F
4,224
Growing degree days, base 50°F
3,201
Growing degree days, base 55°F
2,313
Growing degree days, base 60°F
1,555

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,23501
February1,02202
March825230
April495691
May22052311
June37181594
July3310772
August4263724
September82106475
October37013171
November722027
December1,07102

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 5.7 km from Buffalo Grove. 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 USW00004838 (Chicago Palwaukee AP). Public domain.