Oconto climate

Oconto Frost Dates and Growing Season

NOAA 1991-2020 normals for Oconto 4 W, 7.2 km from Oconto, elevation 660 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Oconto 4 W. 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 9 and the first fall freeze around October 6, a growing season of about 150 days.

Median at 36°F
last May 20, first September 26
Median at 32°F
last May 9, first October 6
Median at 28°F
last April 28, first October 17

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°FJun 2May 29May 26May 23May 20May 18May 14May 10May 5
32°FMay 23May 18May 15May 12May 9May 7May 3Apr 30Apr 25
28°FMay 14May 8May 3Apr 30Apr 28Apr 24Apr 21Apr 17Apr 12
24°FApr 30Apr 25Apr 21Apr 17Apr 15Apr 11Apr 8Apr 4Mar 31
20°FApr 18Apr 13Apr 9Apr 6Apr 3Apr 2Mar 31Mar 26Mar 20
16°FApr 9Apr 4Apr 2Mar 31Mar 28Mar 24Mar 21Mar 17Mar 12

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 11Sep 16Sep 20Sep 23Sep 26Sep 30Oct 2Oct 5Oct 9
32°FSep 22Sep 27Oct 1Oct 3Oct 6Oct 8Oct 12Oct 15Oct 19
28°FOct 1Oct 7Oct 11Oct 15Oct 17Oct 20Oct 24Oct 27Nov 1
24°FOct 14Oct 20Oct 25Oct 28Oct 31Nov 2Nov 5Nov 9Nov 15
20°FOct 29Nov 1Nov 4Nov 7Nov 11Nov 14Nov 17Nov 21Nov 26
16°FNov 5Nov 10Nov 15Nov 18Nov 21Nov 24Nov 28Dec 1Dec 5

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°F148141136132129125121117109
32°F170163158154150146142137130
28°F194187182178174170165160152
24°F221213207202198194191185178
20°F242235230225221217213207201
16°F260254249244240235231226219

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
7,827
Cooling degree days, base 65°F
442
Growing degree days, base 40°F
4,129
Growing degree days, base 45°F
3,135
Growing degree days, base 50°F
2,269
Growing degree days, base 55°F
1,525
Growing degree days, base 60°F
910

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,47400
February1,26300
March1,07006
April670134
May32521206
June8088460
July23162604
August34125556
September18741316
October533378
November88508
December1,28500

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 7.2 km from Oconto. 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 USC00476208 (Oconto 4 W). Public domain.