Pymatuning Central climate

Pymatuning Central Frost Dates and Growing Season

NOAA 1991-2020 normals for Linesville 1 S, 8.1 km from Pymatuning Central, elevation 1030 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Linesville 1 S. 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 30 and the first fall freeze around October 23, a growing season of about 177 days.

Median at 36°F
last May 11, first October 10
Median at 32°F
last April 30, first October 23
Median at 28°F
last April 18, first November 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°FMay 26May 21May 18May 15May 11May 8May 4Apr 30Apr 26
32°FMay 17May 11May 6May 2Apr 30Apr 27Apr 24Apr 21Apr 16
28°FMay 3Apr 28Apr 23Apr 21Apr 18Apr 15Apr 12Apr 8Apr 3
24°FApr 20Apr 16Apr 12Apr 9Apr 6Apr 3Apr 1Mar 30Mar 24
20°FApr 11Apr 5Apr 2Mar 31Mar 29Mar 26Mar 22Mar 19Mar 15
16°FApr 1Mar 29Mar 25Mar 22Mar 19Mar 17Mar 14Mar 10Mar 5

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 27Oct 1Oct 4Oct 7Oct 10Oct 13Oct 15Oct 19Oct 25
32°FOct 6Oct 12Oct 17Oct 20Oct 23Oct 27Oct 31Nov 2Nov 6
28°FOct 23Oct 28Nov 1Nov 2Nov 5Nov 8Nov 11Nov 15Nov 20
24°FNov 4Nov 8Nov 11Nov 14Nov 17Nov 21Nov 24Nov 29Dec 4
20°FNov 11Nov 16Nov 21Nov 25Nov 29Dec 1Dec 5Dec 9Dec 16
16°FNov 21Nov 28Dec 1Dec 4Dec 8Dec 12Dec 16Dec 20Dec 26

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°F172165160156151147142137129
32°F197190186181177172167160154
28°F221214210206201197194188179
24°F245237232229224221216211204
20°F268260254248243239235230224
16°F286279273269263258254247239

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
6,610
Cooling degree days, base 65°F
557
Growing degree days, base 40°F
4,714
Growing degree days, base 45°F
3,602
Growing degree days, base 50°F
2,633
Growing degree days, base 55°F
1,798
Growing degree days, base 60°F
1,101

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,25701
February1,10301
March960015
April561375
May25934269
June63114502
July14189640
August21151595
September12559388
October4366125
November746020
December1,06602

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 8.1 km from Pymatuning Central. 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 USC00365050 (Linesville 1 S). Public domain.