Scott County climate

Scott County Frost Dates and Growing Season

NOAA 1991-2020 normals for Jordan 1SSW, 7.9 km from Scott County, elevation 900 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Jordan 1SSW. 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 May 2 and the first fall freeze around October 5, a growing season of about 153 days.

Median at 36°F
last May 11, first September 27
Median at 32°F
last May 2, first October 5
Median at 28°F
last April 22, first October 16

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°FMay 25May 21May 18May 14May 11May 9May 6May 3Apr 29
32°FMay 18May 12May 9May 5May 2Apr 30Apr 27Apr 22Apr 17
28°FMay 7May 2Apr 29Apr 25Apr 22Apr 18Apr 15Apr 11Apr 7
24°FApr 27Apr 22Apr 18Apr 14Apr 12Apr 8Apr 6Apr 3Mar 30
20°FApr 19Apr 13Apr 9Apr 6Apr 3Apr 1Mar 30Mar 26Mar 19
16°FApr 11Apr 5Apr 2Mar 31Mar 27Mar 24Mar 21Mar 17Mar 12

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°FSep 14Sep 19Sep 22Sep 24Sep 27Sep 30Oct 2Oct 6Oct 10
32°FSep 21Sep 26Sep 29Oct 2Oct 5Oct 8Oct 11Oct 15Oct 19
28°FSep 29Oct 4Oct 9Oct 13Oct 16Oct 19Oct 22Oct 25Oct 30
24°FOct 8Oct 16Oct 20Oct 24Oct 27Oct 30Nov 2Nov 6Nov 11
20°FOct 22Oct 28Oct 31Nov 3Nov 6Nov 8Nov 11Nov 15Nov 21
16°FOct 31Nov 4Nov 8Nov 11Nov 14Nov 17Nov 20Nov 24Nov 29

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°F155149144140137133129123118
32°F173167161157153150146141135
28°F195188183178174169164159150
24°F216209205201197193187182174
20°F235228223219215211207202194
16°F252244238233229225221215207

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
100% 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
8,057
Cooling degree days, base 65°F
532
Growing degree days, base 40°F
4,378
Growing degree days, base 45°F
3,373
Growing degree days, base 50°F
2,478
Growing degree days, base 55°F
1,699
Growing degree days, base 60°F
1,046

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,59300
February1,32000
March1,07109
April621254
May28528241
June52121519
July12195648
August29132567
September17451339
October541590
November959010
December1,40000

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 7.9 km from Scott 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 USC00214176 (Jordan 1SSW). Public domain.