Lawrence County climate

Lawrence County Frost Dates and Growing Season

NOAA 1991-2020 normals for Lawrenceville 2WSW, 0.8 km from Lawrence County, elevation 451 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lawrenceville 2WSW. 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 12 and the first fall freeze around October 25, a growing season of about 193 days.

Median at 36°F
last April 24, first October 16
Median at 32°F
last April 12, first October 25
Median at 28°F
last April 1, first November 3

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

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 2Oct 7Oct 10Oct 13Oct 16Oct 18Oct 20Oct 24Oct 27
32°FOct 12Oct 17Oct 20Oct 23Oct 25Oct 28Oct 30Nov 2Nov 5
28°FOct 22Oct 26Oct 30Nov 1Nov 3Nov 6Nov 9Nov 13Nov 20
24°FOct 31Nov 4Nov 7Nov 11Nov 14Nov 18Nov 22Nov 27Dec 3
20°FNov 8Nov 14Nov 19Nov 23Nov 27Dec 1Dec 4Dec 8Dec 15
16°FNov 17Nov 25Nov 30Dec 3Dec 7Dec 11Dec 17Dec 21Dec 28

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°F191184180175171167163159152
32°F213206202198193189185180172
28°F237229223219214210206201193
24°F263254249244239233229222214
20°F288279272266261255249242233
16°F310301293288283277270264253

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
4,929
Cooling degree days, base 65°F
1,291
Growing degree days, base 40°F
6,430
Growing degree days, base 45°F
5,132
Growing degree days, base 50°F
3,971
Growing degree days, base 55°F
2,943
Growing degree days, base 60°F
2,049

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,07905
February86109
March664363
April32617201
May101107473
June9283724
July1371835
August2318781
September50161562
October28330251
November612157
December94209

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 0.8 km from Lawrence 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 USC00114957 (Lawrenceville 2WSW). Public domain.