Mott climate

Mott Frost Dates and Growing Season

NOAA 1991-2020 normals for Mott, 0.5 km from Mott, elevation 2426 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mott. 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 16 and the first fall freeze around September 25, a growing season of about 129 days.

Median at 36°F
last May 27, first September 15
Median at 32°F
last May 16, first September 25
Median at 28°F
last May 7, first October 3

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

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 2Sep 6Sep 9Sep 12Sep 15Sep 18Sep 20Sep 24Sep 28
32°FSep 11Sep 17Sep 19Sep 22Sep 25Sep 27Oct 1Oct 3Oct 7
28°FSep 19Sep 24Sep 27Oct 1Oct 3Oct 5Oct 8Oct 12Oct 17
24°FSep 26Oct 1Oct 4Oct 8Oct 12Oct 15Oct 18Oct 21Oct 26
20°FOct 4Oct 10Oct 15Oct 18Oct 21Oct 24Oct 28Oct 30Nov 4
16°FOct 15Oct 20Oct 24Oct 28Oct 30Nov 1Nov 4Nov 8Nov 13

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°F1281221171131091071039993
32°F147141136132129125122118111
28°F167160155151148144139134128
24°F185180175170166162157153146
20°F204198193188184180176170164
16°F224216211207202197193188181

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
8,535
Cooling degree days, base 65°F
481
Growing degree days, base 40°F
3,969
Growing degree days, base 45°F
3,016
Growing degree days, base 50°F
2,189
Growing degree days, base 55°F
1,481
Growing degree days, base 60°F
905

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,54400
February1,29600
March1,09302
April697135
May37110175
June11272412
July34191623
August45161582
September22745295
October645160
November1,05004
December1,42300

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 0.5 km from Mott. 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 USC00326155 (Mott). Public domain.