Jackson climate

Jackson Frost Dates and Growing Season

NOAA 1991-2020 normals for Jackson Hawkins Fld, 5.4 km from Jackson, elevation 342 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Jackson Hawkins Fld. 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 6 and the first fall freeze around November 19, a growing season of about 258 days.

Median at 36°F
last March 20, first November 9
Median at 32°F
last March 6, first November 19
Median at 28°F
last February 19, first December 4

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 7Apr 2Mar 29Mar 24Mar 20Mar 17Mar 13Mar 8Mar 2
32°FMar 24Mar 17Mar 13Mar 10Mar 6Mar 2Feb 27Feb 22Feb 15
28°FMar 13Mar 6Mar 1Feb 25Feb 19Feb 14Feb 7Jan 31Jan 23
24°FFeb 28Feb 20Feb 12Feb 4Jan 31Jan 27Jan 20Jan 13Jan 2
20°FFeb 18Feb 5Feb 1Jan 27Jan 21Jan 15Jan 11Jan 4Dec 26
16°FFeb 6Feb 1Jan 28Jan 22Jan 17Jan 13Jan 11Jan 6Jan 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 27Nov 1Nov 3Nov 6Nov 9Nov 11Nov 15Nov 19Nov 24
32°FNov 4Nov 8Nov 12Nov 15Nov 19Nov 23Nov 27Dec 2Dec 10
28°FNov 11Nov 18Nov 24Nov 30Dec 4Dec 9Dec 17Dec 26Jan 3
24°FNov 28Dec 5Dec 13Dec 23Dec 29Jan 2Jan 6Jan 13Jan 24
20°FDec 12Dec 24Dec 31Jan 2Jan 6Jan 11Jan 16Jan 23Feb 3
16°FJan 1Jan 3Jan 7Jan 10Jan 12Jan 16Jan 21Jan 29Feb 3

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°F259250244239235230225219210
32°F289278271265258254248242236
28°F325313305297290283276269257
24°F360348339333327318311303289
20°F365365365365360350342334322
16°F365365365365365365365365347

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
92% of years
20°F or colder
58% of years
16°F or colder
21% 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
2,123
Cooling degree days, base 65°F
2,523
Growing degree days, base 40°F
9,608
Growing degree days, base 45°F
7,916
Growing degree days, base 50°F
6,348
Growing degree days, base 55°F
4,918
Growing degree days, base 60°F
3,637

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January550694
February39211133
March23036297
April8098470
May10277732
June0459909
July05441,009
August05421,007
September2382829
October75139530
November29319218
December49110119

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 5.4 km from Jackson. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USW00013927 (Jackson Hawkins Fld). Public domain.