Plum City climate

Plum City Frost Dates and Growing Season

NOAA 1991-2020 normals for Durand, 16.9 km from Plum City, elevation 705 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Durand. 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 1 and the first fall freeze around October 10, a growing season of about 162 days.

Median at 36°F
last May 10, first October 1
Median at 32°F
last May 1, first October 10
Median at 28°F
last April 20, first October 22

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 24May 19May 16May 13May 10May 7May 5May 2Apr 28
32°FMay 15May 9May 6May 4May 1Apr 29Apr 26Apr 22Apr 17
28°FMay 3Apr 29Apr 25Apr 22Apr 20Apr 17Apr 14Apr 10Apr 7
24°FApr 24Apr 20Apr 16Apr 12Apr 9Apr 7Apr 4Apr 2Mar 28
20°FApr 15Apr 9Apr 5Apr 3Apr 2Mar 31Mar 27Mar 23Mar 17
16°FApr 7Apr 2Mar 31Mar 29Mar 26Mar 22Mar 18Mar 14Mar 9

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 17Sep 22Sep 25Sep 28Oct 1Oct 3Oct 5Oct 9Oct 13
32°FSep 26Oct 1Oct 4Oct 7Oct 10Oct 12Oct 16Oct 19Oct 25
28°FOct 7Oct 12Oct 16Oct 20Oct 22Oct 25Oct 28Oct 31Nov 4
24°FOct 18Oct 23Oct 27Oct 30Nov 1Nov 3Nov 6Nov 9Nov 13
20°FOct 29Nov 1Nov 3Nov 6Nov 8Nov 11Nov 14Nov 17Nov 22
16°FNov 4Nov 8Nov 11Nov 14Nov 16Nov 20Nov 22Nov 25Nov 30

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°F159153148145141137133128120
32°F181175170166162158154148139
28°F203197192188184181177172163
24°F221214210206203199195191184
20°F241233228224220216213208202
16°F256249245241236232228223217

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
7,784
Cooling degree days, base 65°F
578
Growing degree days, base 40°F
4,530
Growing degree days, base 45°F
3,503
Growing degree days, base 50°F
2,590
Growing degree days, base 55°F
1,796
Growing degree days, base 60°F
1,119

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,56300
February1,30300
March1,035114
April604156
May26328259
June44113519
July8211668
August19163609
September15455359
October511698
November93309
December1,34700

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 16.9 km from Plum City. 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 USC00472279 (Durand). Public domain.