Logan County climate

Logan County Frost Dates and Growing Season

NOAA 1991-2020 normals for Logan, 5.8 km from Logan County, elevation 672 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Logan. 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 8 and the first fall freeze around November 2, a growing season of about 208 days.

Median at 36°F
last April 21, first October 25
Median at 32°F
last April 8, first November 2
Median at 28°F
last March 28, first November 13

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 6May 1Apr 27Apr 23Apr 21Apr 18Apr 15Apr 11Apr 5
32°FApr 21Apr 17Apr 14Apr 11Apr 8Apr 5Apr 2Mar 31Mar 25
28°FApr 12Apr 5Apr 2Mar 31Mar 28Mar 24Mar 20Mar 16Mar 8
24°FMar 31Mar 25Mar 20Mar 17Mar 13Mar 10Mar 5Feb 28Feb 21
20°FMar 20Mar 14Mar 9Mar 4Feb 28Feb 26Feb 19Feb 11Feb 3
16°FMar 13Mar 3Feb 27Feb 19Feb 12Feb 7Feb 3Jan 29Jan 19

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°FOct 11Oct 16Oct 18Oct 22Oct 25Oct 27Oct 30Nov 1Nov 5
32°FOct 20Oct 25Oct 29Nov 1Nov 2Nov 4Nov 7Nov 10Nov 15
28°FOct 31Nov 4Nov 7Nov 10Nov 13Nov 16Nov 19Nov 24Dec 1
24°FNov 10Nov 15Nov 19Nov 24Nov 28Dec 1Dec 4Dec 9Dec 18
20°FNov 21Nov 28Dec 2Dec 7Dec 12Dec 18Dec 23Dec 29Jan 5
16°FDec 5Dec 11Dec 19Dec 24Dec 29Jan 2Jan 7Jan 13Jan 21

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°F203197193189186181177172166
32°F228220216212208204200195189
28°F253246240234230226221218211
24°F285277270264258251247241234
20°F319308301294288281275266256
16°F343331325318312306301293281

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
97% 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
4,139
Cooling degree days, base 65°F
1,421
Growing degree days, base 40°F
6,966
Growing degree days, base 45°F
5,555
Growing degree days, base 50°F
4,301
Growing degree days, base 55°F
3,196
Growing degree days, base 60°F
2,238

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January913013
February724020
March567487
April25631265
May82124509
June6282726
July0395860
August0361826
September26190614
October23532284
November535173
December795024

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 5.8 km from Logan County. 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 USC00465353 (Logan). Public domain.