Nisswa climate

Nisswa Frost Dates and Growing Season

NOAA 1991-2020 normals for Gull Lake Dam, 13.3 km from Nisswa, elevation 1215 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Gull Lake Dam. 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 2 and the first fall freeze around October 6, a growing season of about 156 days.

Median at 36°F
last May 11, first September 28
Median at 32°F
last May 2, first October 6
Median at 28°F
last April 23, first October 19

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 11May 9May 6May 4May 1
32°FMay 14May 10May 7May 4May 2Apr 30Apr 29Apr 26Apr 21
28°FMay 4Apr 30Apr 28Apr 25Apr 23Apr 20Apr 18Apr 15Apr 11
24°FApr 26Apr 22Apr 19Apr 17Apr 15Apr 13Apr 10Apr 7Apr 4
20°FApr 20Apr 15Apr 12Apr 10Apr 7Apr 5Apr 2Mar 31Mar 26
16°FApr 14Apr 9Apr 6Apr 3Apr 1Mar 31Mar 27Mar 23Mar 17

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 15Sep 20Sep 23Sep 26Sep 28Sep 30Oct 2Oct 5Oct 10
32°FSep 25Sep 30Oct 2Oct 4Oct 6Oct 10Oct 13Oct 16Oct 21
28°FOct 5Oct 10Oct 13Oct 16Oct 19Oct 22Oct 24Oct 28Nov 1
24°FOct 14Oct 20Oct 23Oct 27Oct 30Nov 1Nov 3Nov 6Nov 11
20°FOct 27Oct 30Nov 1Nov 3Nov 6Nov 8Nov 11Nov 14Nov 18
16°FNov 1Nov 5Nov 8Nov 11Nov 14Nov 16Nov 19Nov 23Nov 27

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°F155150146142139136133129122
32°F173167164160156153149145140
28°F194188184180176173169165159
24°F213207202199195192188184178
20°F228222218214211208204200194
16°F243238233228225221217213207

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
9,018
Cooling degree days, base 65°F
423
Growing degree days, base 40°F
3,951
Growing degree days, base 45°F
3,018
Growing degree days, base 50°F
2,192
Growing degree days, base 55°F
1,479
Growing degree days, base 60°F
882

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,75800
February1,44800
March1,19702
April725029
May32218208
June7483460
July20173618
August34120550
September22328275
October638149
November1,05503
December1,52700

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 13.3 km from Nisswa. 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 USC00213411 (Gull Lake Dam). Public domain.