Ligonier climate

Ligonier Frost Dates and Growing Season

NOAA 1991-2020 normals for Laurel Mtn, 6.3 km from Ligonier, elevation 2760 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Laurel Mtn. 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 26 and the first fall freeze around October 17, a growing season of about 172 days.

Median at 36°F
last May 7, first October 5
Median at 32°F
last April 26, first October 17
Median at 28°F
last April 16, first October 29

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 23May 18May 14May 10May 7May 3Apr 30Apr 27Apr 23
32°FMay 13May 7May 2Apr 30Apr 26Apr 23Apr 21Apr 18Apr 13
28°FApr 30Apr 24Apr 21Apr 19Apr 16Apr 13Apr 10Apr 7Apr 2
24°FApr 19Apr 14Apr 11Apr 8Apr 6Apr 4Apr 1Mar 30Mar 22
20°FApr 9Apr 5Apr 3Mar 31Mar 28Mar 24Mar 20Mar 16Mar 9
16°FMar 31Mar 27Mar 24Mar 20Mar 17Mar 14Mar 9Mar 5Feb 28

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 23Sep 28Oct 1Oct 3Oct 5Oct 8Oct 11Oct 14Oct 18
32°FOct 4Oct 7Oct 11Oct 14Oct 17Oct 20Oct 22Oct 26Oct 29
28°FOct 15Oct 20Oct 23Oct 27Oct 29Nov 1Nov 4Nov 7Nov 14
24°FOct 31Nov 2Nov 5Nov 8Nov 11Nov 14Nov 18Nov 22Nov 29
20°FNov 7Nov 13Nov 16Nov 20Nov 23Nov 27Dec 1Dec 5Dec 12
16°FNov 16Nov 23Nov 28Dec 1Dec 5Dec 10Dec 15Dec 22Dec 29

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°F168163158154150146142138131
32°F190184179176172168164158153
28°F216209203199196192188183176
24°F241233227223220216212207200
20°F266257252247242238234228221
16°F290282275269264258253247239

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
6,045
Cooling degree days, base 65°F
478
Growing degree days, base 40°F
4,874
Growing degree days, base 45°F
3,692
Growing degree days, base 50°F
2,654
Growing degree days, base 55°F
1,764
Growing degree days, base 60°F
1,034

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,17002
February99304
March849131
April4717119
May22629281
June5898491
July10171626
August18132580
September13736355
October4193133
November707027
December99006

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 6.3 km from Ligonier. 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 USC00364836 (Laurel Mtn). Public domain.