Lonoke climate

Lonoke Frost Dates and Growing Season

NOAA 1991-2020 normals for Keo, 21.8 km from Lonoke, elevation 231 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Keo. 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 21 and the first fall freeze around November 9, a growing season of about 235 days.

Median at 36°F
last April 2, first October 30
Median at 32°F
last March 21, first November 9
Median at 28°F
last March 8, 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 18Apr 11Apr 8Apr 5Apr 2Mar 31Mar 27Mar 23Mar 16
32°FApr 6Apr 1Mar 28Mar 24Mar 21Mar 18Mar 13Mar 9Mar 2
28°FMar 26Mar 20Mar 16Mar 12Mar 8Mar 4Mar 1Feb 26Feb 18
24°FMar 16Mar 9Mar 4Mar 1Feb 26Feb 21Feb 15Feb 8Jan 31
20°FMar 6Feb 27Feb 21Feb 15Feb 7Feb 1Jan 28Jan 21Jan 9
16°FFeb 25Feb 14Feb 4Jan 30Jan 26Jan 20Jan 15Jan 7Jan 1

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 18Oct 22Oct 25Oct 27Oct 30Nov 1Nov 4Nov 7Nov 12
32°FOct 27Nov 1Nov 3Nov 6Nov 9Nov 12Nov 16Nov 21Nov 26
28°FNov 4Nov 9Nov 14Nov 18Nov 22Nov 26Dec 1Dec 5Dec 12
24°FNov 15Nov 23Nov 28Dec 3Dec 8Dec 14Dec 20Dec 27Jan 4
20°FDec 2Dec 12Dec 20Dec 25Dec 30Jan 3Jan 8Jan 15Jan 28
16°FDec 15Dec 24Dec 30Jan 2Jan 7Jan 12Jan 16Jan 23Feb 5

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°F234225220216211207202196189
32°F258251245240235230224218211
28°F284275269264258253247241233
24°F318305298292286280273266257
20°F352340332326319312305299287
16°F365365363354347340333323311

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
96% of years
16°F or colder
72% 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
3,216
Cooling degree days, base 65°F
1,825
Growing degree days, base 40°F
8,012
Growing degree days, base 45°F
6,473
Growing degree days, base 50°F
5,083
Growing degree days, base 55°F
3,844
Growing degree days, base 60°F
2,755

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January766027
February581149
March39910160
April15552357
May31184619
June0369819
July0465930
August0429894
September14242678
October14964389
November4337123
December687139

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 21.8 km from Lonoke. 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 USC00033862 (Keo). Public domain.