Bagley climate

Bagley Frost Dates and Growing Season

NOAA 1991-2020 normals for Fosston 1 E, 25 km from Bagley, elevation 1300 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Fosston 1 E. 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 15 and the first fall freeze around September 26, a growing season of about 132 days.

Median at 36°F
last May 27, first September 14
Median at 32°F
last May 15, first September 26
Median at 28°F
last May 4, first October 5

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 17Jun 6Jun 2May 30May 27May 25May 22May 18May 13
32°FMay 30May 25May 22May 18May 15May 12May 9May 5May 2
28°FMay 20May 14May 10May 6May 4May 1Apr 29Apr 25Apr 20
24°FMay 9May 3Apr 30Apr 27Apr 24Apr 21Apr 18Apr 15Apr 9
20°FApr 29Apr 24Apr 20Apr 17Apr 15Apr 12Apr 9Apr 6Apr 3
16°FApr 22Apr 17Apr 13Apr 10Apr 8Apr 5Apr 3Mar 31Mar 24

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°FAug 28Sep 2Sep 7Sep 11Sep 14Sep 17Sep 20Sep 23Sep 28
32°FSep 10Sep 16Sep 20Sep 23Sep 26Sep 29Oct 1Oct 4Oct 8
28°FSep 23Sep 27Sep 30Oct 2Oct 5Oct 9Oct 12Oct 16Oct 22
24°FOct 2Oct 6Oct 10Oct 15Oct 18Oct 21Oct 25Oct 28Nov 1
20°FOct 10Oct 18Oct 22Oct 26Oct 29Oct 31Nov 2Nov 5Nov 10
16°FOct 21Oct 27Oct 31Nov 2Nov 5Nov 7Nov 10Nov 13Nov 17

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°F130123117113109103979079
32°F152146141136132128123117109
28°F173166161156152148143138131
24°F194188182177173169164159152
20°F214207202197194190186180173
16°F229222218213210206201196189

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
9,778
Cooling degree days, base 65°F
287
Growing degree days, base 40°F
3,547
Growing degree days, base 45°F
2,656
Growing degree days, base 50°F
1,871
Growing degree days, base 55°F
1,195
Growing degree days, base 60°F
657

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,84900
February1,54600
March1,27602
April762029
May37714181
June11961395
July52108521
August7877464
September27726234
October690144
November1,14302
December1,61000

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 25 km from Bagley. 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 USC00212916 (Fosston 1 E). Public domain.