Independence climate

Independence Frost Dates and Growing Season

NOAA 1991-2020 normals for Sparta 3.5 Ssw, 18.2 km from Independence, elevation 3011 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Sparta 3.5 Ssw. 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 April 22 and the first fall freeze around October 22, a growing season of about 180 days.

Median at 36°F
last May 5, first October 11
Median at 32°F
last April 22, first October 22
Median at 28°F
last April 6, first October 31

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 21May 16May 12May 8May 5May 2Apr 29Apr 24Apr 18
32°FMay 11May 5Apr 30Apr 25Apr 22Apr 18Apr 14Apr 10Apr 6
28°FApr 27Apr 19Apr 13Apr 10Apr 6Apr 4Apr 1Mar 30Mar 23
24°FApr 10Apr 5Apr 2Mar 31Mar 28Mar 24Mar 20Mar 16Mar 11
20°FApr 2Mar 28Mar 23Mar 19Mar 15Mar 11Mar 7Mar 2Feb 24
16°FMar 24Mar 18Mar 12Mar 7Mar 2Feb 28Feb 22Feb 16Feb 7

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 27Oct 2Oct 6Oct 9Oct 11Oct 14Oct 17Oct 20Oct 24
32°FOct 8Oct 13Oct 16Oct 19Oct 22Oct 24Oct 26Oct 29Nov 3
28°FOct 18Oct 22Oct 25Oct 28Oct 31Nov 1Nov 5Nov 9Nov 14
24°FOct 27Nov 1Nov 3Nov 6Nov 9Nov 12Nov 15Nov 20Nov 28
20°FNov 5Nov 10Nov 14Nov 17Nov 21Nov 25Dec 1Dec 4Dec 12
16°FNov 15Nov 21Nov 27Dec 1Dec 4Dec 9Dec 15Dec 22Dec 31

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°F177171165160156152147142135
32°F202193188184180175170164156
28°F225218213209205200194189180
24°F252244237232227223218213205
20°F280271263257253247241234226
16°F309299292284279272265258249

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
5,148
Cooling degree days, base 65°F
651
Growing degree days, base 40°F
5,389
Growing degree days, base 45°F
4,105
Growing degree days, base 50°F
3,003
Growing degree days, base 55°F
2,057
Growing degree days, base 60°F
1,273

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January97901
February82906
March712032
April4086127
May18123321
June27130553
July0237702
August6187646
September9258416
October3669162
November649029
December89908

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 18.2 km from Independence. 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 USC00318158 (Sparta 3.5 Ssw). Public domain.