Kimball climate

Kimball Frost Dates and Growing Season

NOAA 1991-2020 normals for Kimball 2NE, 2.6 km from Kimball, elevation 4708 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Kimball 2NE. 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 15 and the first fall freeze around September 26, a growing season of about 132 days.

Median at 36°F
last May 28, first September 18
Median at 32°F
last May 15, first September 26
Median at 28°F
last May 6, first October 6

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

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°F12912311911611210910510093
32°F150143139135132128124120113
28°F171164159156153149144139134
24°F190185180176172169165161156
20°F213205201196192188183178171
16°F236228222217213208204198190

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
7,108
Cooling degree days, base 65°F
453
Growing degree days, base 40°F
4,191
Growing degree days, base 45°F
3,142
Growing degree days, base 50°F
2,259
Growing degree days, base 55°F
1,523
Growing degree days, base 60°F
919

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,18900
February1,03201
March87609
April645036
May3688176
June9274436
July16195645
August33139572
September19136314
October578066
November90306
December1,18700

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 2.6 km from Kimball. 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 USC00254440 (Kimball 2NE). Public domain.