Lawrence County climate

Lawrence County Frost Dates and Growing Season

NOAA 1991-2020 normals for Monticello, 0.2 km from Lawrence County, elevation 191 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Monticello. 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 12 and the first fall freeze around November 10, a growing season of about 242 days.

Median at 36°F
last March 27, first November 1
Median at 32°F
last March 12, first November 10
Median at 28°F
last February 27, first November 22

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

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 16Oct 21Oct 25Oct 29Nov 1Nov 4Nov 7Nov 11Nov 18
32°FOct 23Oct 31Nov 3Nov 6Nov 10Nov 14Nov 19Nov 26Dec 3
28°FOct 31Nov 6Nov 11Nov 16Nov 22Nov 28Dec 3Dec 9Dec 25
24°FNov 9Nov 20Dec 1Dec 5Dec 12Dec 24Jan 1Jan 6Jan 16
20°FNov 26Dec 6Dec 19Dec 28Jan 2Jan 7Jan 12Jan 18Jan 31
16°FDec 2Dec 21Dec 31Jan 4Jan 8Jan 13Jan 19Jan 24Feb 1

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°F245235227222217212207201194
32°F270261253247242236230222212
28°F307295286279272265258250241
24°F349334327317309302294283270
20°F365365364353343335329318306
16°F365365365365365365359344333

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
97% of years
20°F or colder
76% of years
16°F or colder
40% 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
1,893
Cooling degree days, base 65°F
2,726
Growing degree days, base 40°F
10,009
Growing degree days, base 45°F
8,280
Growing degree days, base 50°F
6,663
Growing degree days, base 55°F
5,195
Growing degree days, base 60°F
3,878

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January5076102
February34312154
March20351332
April70127508
May7302760
June0480930
July05751,040
August05661,031
September2408856
October69152551
November25431257
December43916142

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 0.2 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 USC00225987 (Monticello). Public domain.