Ashdown climate

Ashdown Frost Dates and Growing Season

NOAA 1991-2020 normals for Ashdown 4 Sse, 6.7 km from Ashdown, elevation 320 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Ashdown 4 Sse. 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 24 and the first fall freeze around November 11, a growing season of about 233 days.

Median at 36°F
last April 5, first November 3
Median at 32°F
last March 24, first November 11
Median at 28°F
last March 11, first November 21

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

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 21Oct 26Oct 30Nov 1Nov 3Nov 5Nov 8Nov 12Nov 18
32°FOct 30Nov 2Nov 5Nov 7Nov 11Nov 14Nov 18Nov 23Nov 28
28°FNov 5Nov 9Nov 13Nov 17Nov 21Nov 25Nov 30Dec 3Dec 10
24°FNov 13Nov 20Nov 25Nov 30Dec 4Dec 9Dec 16Dec 26Jan 1
20°FNov 26Dec 3Dec 12Dec 20Dec 25Dec 31Jan 4Jan 9Jan 19
16°FDec 11Dec 23Dec 30Jan 1Jan 6Jan 10Jan 15Jan 21Feb 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°F232225220215211207203197192
32°F255247242237233228223217210
28°F281272265260255250245239230
24°F318305296290284277271263255
20°F353341334326319312303294285
16°F365365365358351342335329315

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
68% 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
2,853
Cooling degree days, base 65°F
2,121
Growing degree days, base 40°F
8,559
Growing degree days, base 45°F
6,959
Growing degree days, base 50°F
5,505
Growing degree days, base 55°F
4,218
Growing degree days, base 60°F
3,085

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January690135
February521257
March3578178
April13652372
May27193631
June0405855
July05351,000
August0521985
September6304748
October11393449
November3907143
December613152

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 6.7 km from Ashdown. 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 USC00030286 (Ashdown 4 Sse). Public domain.