Independence climate

Independence Frost Dates and Growing Season

NOAA 1991-2020 normals for Blair, 16.8 km from Independence, elevation 855 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Blair. 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 9 and the first fall freeze around October 1, a growing season of about 143 days.

Median at 36°F
last May 20, first September 22
Median at 32°F
last May 9, first October 1
Median at 28°F
last April 30, first October 8

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°FJun 4May 29May 26May 23May 20May 17May 14May 10May 6
32°FMay 23May 18May 15May 12May 9May 6May 4May 1Apr 28
28°FMay 13May 8May 4May 2Apr 30Apr 27Apr 24Apr 21Apr 17
24°FMay 2Apr 28Apr 24Apr 21Apr 19Apr 16Apr 13Apr 9Apr 3
20°FApr 22Apr 18Apr 14Apr 11Apr 8Apr 5Apr 3Mar 31Mar 25
16°FApr 14Apr 7Apr 4Apr 2Mar 31Mar 27Mar 24Mar 19Mar 14

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 9Sep 14Sep 17Sep 19Sep 22Sep 25Sep 28Oct 1Oct 4
32°FSep 18Sep 22Sep 25Sep 28Oct 1Oct 3Oct 5Oct 8Oct 11
28°FSep 26Oct 1Oct 4Oct 6Oct 8Oct 10Oct 13Oct 16Oct 20
24°FOct 6Oct 11Oct 14Oct 17Oct 19Oct 21Oct 24Oct 27Nov 1
20°FOct 17Oct 21Oct 24Oct 27Oct 30Nov 1Nov 3Nov 7Nov 13
16°FOct 28Nov 1Nov 3Nov 6Nov 9Nov 12Nov 15Nov 20Nov 25

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°F144138134129125122117111104
32°F161155151147143140136132125
28°F180174170166162159155151145
24°F202196192187183180175171165
20°F224217212208204200196191184
16°F246239233230225221217211204

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
8,094
Cooling degree days, base 65°F
482
Growing degree days, base 40°F
4,194
Growing degree days, base 45°F
3,208
Growing degree days, base 50°F
2,335
Growing degree days, base 55°F
1,583
Growing degree days, base 60°F
959

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,57900
February1,29500
March1,05306
April633249
May29722227
June71112491
July19176621
August37124552
September19744312
October583369
November95607
December1,37500

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 16.8 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 USC00470882 (Blair). Public domain.