Interlochen climate

Interlochen Frost Dates and Growing Season

NOAA 1991-2020 normals for Traverse City Munson, 16.1 km from Interlochen, elevation 635 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Traverse City Munson. 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 15, a growing season of about 156 days.

Median at 36°F
last May 22, first October 3
Median at 32°F
last May 9, first October 15
Median at 28°F
last April 28, first October 30

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

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 21Sep 26Sep 29Oct 1Oct 3Oct 6Oct 9Oct 12Oct 17
32°FOct 1Oct 6Oct 9Oct 12Oct 15Oct 18Oct 22Oct 26Nov 1
28°FOct 15Oct 19Oct 24Oct 27Oct 30Nov 1Nov 4Nov 7Nov 12
24°FOct 28Nov 1Nov 4Nov 7Nov 10Nov 12Nov 16Nov 19Nov 26
20°FNov 7Nov 12Nov 16Nov 19Nov 22Nov 26Nov 30Dec 3Dec 9
16°FNov 17Nov 22Nov 27Dec 1Dec 3Dec 7Dec 11Dec 16Dec 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°F152145140136132128124120113
32°F177171165160156153148144138
28°F201194190185181177174169162
24°F229221216212208204200195189
20°F251243238234230226221217210
16°F273266260254250246241235229

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
7,610
Cooling degree days, base 65°F
399
Growing degree days, base 40°F
4,001
Growing degree days, base 45°F
3,022
Growing degree days, base 50°F
2,173
Growing degree days, base 55°F
1,443
Growing degree days, base 60°F
841

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,34700
February1,20500
March1,08418
April714135
May36616180
June10773418
July31152586
August38116542
September18337314
October525483
November84607
December1,16400

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 16.1 km from Interlochen. 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 USC00208249 (Traverse City Munson). Public domain.