Lawrence County climate

Lawrence County Frost Dates and Growing Season

NOAA 1991-2020 normals for Alicia 2NNE, 13.1 km from Lawrence County, elevation 258 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Alicia 2NNE. 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 March 27 and the first fall freeze around November 5, a growing season of about 224 days.

Median at 36°F
last April 4, first October 27
Median at 32°F
last March 27, first November 5
Median at 28°F
last March 13, first November 17

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

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 15Oct 19Oct 21Oct 24Oct 27Oct 29Nov 1Nov 4Nov 10
32°FOct 22Oct 28Nov 1Nov 3Nov 5Nov 8Nov 11Nov 16Nov 23
28°FNov 1Nov 5Nov 9Nov 13Nov 17Nov 21Nov 28Dec 1Dec 7
24°FNov 10Nov 17Nov 22Nov 27Dec 1Dec 5Dec 9Dec 17Dec 25
20°FNov 22Nov 30Dec 6Dec 12Dec 19Dec 24Dec 29Jan 4Jan 13
16°FDec 6Dec 16Dec 23Dec 29Jan 1Jan 6Jan 12Jan 18Jan 30

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°F225217212208204201197192185
32°F249240234229224220216210204
28°F277266260254249244239233225
24°F301293286280274269262256247
20°F330320313306302297291282270
16°F360349339333327321314307299

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
93% 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
3,857
Cooling degree days, base 65°F
1,679
Growing degree days, base 40°F
7,413
Growing degree days, base 45°F
5,970
Growing degree days, base 50°F
4,682
Growing degree days, base 55°F
3,538
Growing degree days, base 60°F
2,537

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January893011
February694021
March5004102
April21128287
May49153569
June1373822
July0456921
August0408873
September23206633
October19048338
November505490
December790016

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 13.1 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 USC00030064 (Alicia 2NNE). Public domain.