Stromsburg climate

Stromsburg Frost Dates and Growing Season

NOAA 1991-2020 normals for Osceola, 8.8 km from Stromsburg, elevation 1662 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Osceola. 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 April 25 and the first fall freeze around October 14, a growing season of about 170 days.

Median at 36°F
last May 4, first October 4
Median at 32°F
last April 25, first October 14
Median at 28°F
last April 16, first October 21

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 16May 12May 9May 6May 4May 2Apr 30Apr 26Apr 22
32°FMay 8May 3Apr 30Apr 28Apr 25Apr 22Apr 20Apr 17Apr 12
28°FApr 29Apr 24Apr 21Apr 18Apr 16Apr 13Apr 10Apr 7Apr 3
24°FApr 21Apr 17Apr 12Apr 10Apr 7Apr 4Apr 1Mar 29Mar 22
20°FApr 13Apr 8Apr 5Apr 1Mar 30Mar 27Mar 22Mar 18Mar 12
16°FApr 6Mar 31Mar 28Mar 24Mar 20Mar 16Mar 12Mar 8Mar 3

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 22Sep 26Sep 30Oct 2Oct 4Oct 6Oct 9Oct 12Oct 16
32°FSep 29Oct 4Oct 7Oct 11Oct 14Oct 16Oct 19Oct 21Oct 24
28°FOct 6Oct 13Oct 16Oct 19Oct 21Oct 24Oct 27Oct 31Nov 4
24°FOct 16Oct 21Oct 25Oct 28Oct 31Nov 2Nov 5Nov 9Nov 13
20°FOct 24Oct 30Nov 1Nov 5Nov 8Nov 10Nov 13Nov 18Nov 23
16°FOct 31Nov 4Nov 8Nov 11Nov 14Nov 18Nov 21Nov 25Dec 1

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°F170164160157153150146142137
32°F188181178174170167163158152
28°F208201196192189185181176169
24°F227220215210206202197192186
20°F245238234229224219214209201
16°F263255250245240236230224216

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
6,259
Cooling degree days, base 65°F
993
Growing degree days, base 40°F
5,523
Growing degree days, base 45°F
4,364
Growing degree days, base 50°F
3,333
Growing degree days, base 55°F
2,425
Growing degree days, base 60°F
1,644

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,28000
February1,04403
March810130
April4628120
May17467371
June18215646
July3325787
August7255713
September94110470
October40112168
November795024
December1,17001

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 8.8 km from Stromsburg. 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 USC00256375 (Osceola). Public domain.