Linntown climate

Linntown Frost Dates and Growing Season

NOAA 1991-2020 normals for Lewisburg, 2.1 km from Linntown, elevation 500 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lewisburg. 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 20, a growing season of about 176 days.

Median at 36°F
last May 6, first October 7
Median at 32°F
last April 26, first October 20
Median at 28°F
last April 14, first November 1

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 21May 17May 12May 9May 6May 3Apr 30Apr 27Apr 23
32°FMay 11May 5May 2Apr 29Apr 26Apr 23Apr 20Apr 17Apr 13
28°FApr 28Apr 23Apr 19Apr 16Apr 14Apr 10Apr 8Apr 4Mar 31
24°FApr 15Apr 10Apr 6Apr 4Apr 2Mar 30Mar 27Mar 23Mar 17
20°FApr 4Apr 1Mar 28Mar 25Mar 21Mar 18Mar 15Mar 10Mar 6
16°FMar 26Mar 20Mar 17Mar 14Mar 10Mar 7Mar 5Feb 28Feb 22

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 25Sep 30Oct 2Oct 5Oct 7Oct 10Oct 13Oct 16Oct 21
32°FOct 5Oct 9Oct 13Oct 17Oct 20Oct 23Oct 26Oct 29Nov 1
28°FOct 17Oct 22Oct 26Oct 29Nov 1Nov 2Nov 4Nov 7Nov 13
24°FOct 31Nov 2Nov 5Nov 8Nov 11Nov 14Nov 17Nov 20Nov 25
20°FNov 8Nov 13Nov 16Nov 20Nov 23Nov 27Nov 30Dec 3Dec 11
16°FNov 18Nov 26Dec 1Dec 3Dec 6Dec 12Dec 17Dec 22Dec 31

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°F173166162158154150146140133
32°F195188183180176172166161156
28°F217212207204200196192186180
24°F244236231228223219216210203
20°F269262256251247242238232225
16°F297289283277273268262256249

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
6,004
Cooling degree days, base 65°F
703
Growing degree days, base 40°F
5,090
Growing degree days, base 45°F
3,936
Growing degree days, base 50°F
2,923
Growing degree days, base 55°F
2,041
Growing degree days, base 60°F
1,301

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,17601
February1,00501
March851017
April474698
May19738317
June33139557
July3248710
August9198654
September10266416
October4077136
November723015
December1,02503

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 2.1 km from Linntown. 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 USC00364976 (Lewisburg). Public domain.