Adams County climate

Adams County Frost Dates and Growing Season

NOAA 1991-2020 normals for Hettinger Muni AP, 13.5 km from Adams County, elevation 2705 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Hettinger Muni AP. 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 24 and the first fall freeze around September 18, a growing season of about 115 days.

Median at 36°F
last June 4, first September 6
Median at 32°F
last May 24, first September 18
Median at 28°F
last May 13, first September 27

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

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°FAug 22Aug 27Sep 1Sep 3Sep 6Sep 9Sep 12Sep 16Sep 20
32°FSep 1Sep 6Sep 10Sep 14Sep 18Sep 20Sep 23Sep 27Oct 1
28°FSep 11Sep 18Sep 22Sep 25Sep 27Sep 30Oct 3Oct 6Oct 11
24°FSep 22Sep 26Sep 30Oct 4Oct 7Oct 9Oct 12Oct 16Oct 20
20°FSep 29Oct 5Oct 9Oct 13Oct 15Oct 18Oct 21Oct 25Oct 29
16°FOct 9Oct 15Oct 18Oct 21Oct 24Oct 28Oct 31Nov 3Nov 8

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°F113106101969287837667
32°F13512912311911511110610092
28°F154147142139135131126121114
24°F174168163159154150146141133
20°F194187181178174170166160153
16°F215207202197193189184178170

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
8,604
Cooling degree days, base 65°F
386
Growing degree days, base 40°F
3,749
Growing degree days, base 45°F
2,805
Growing degree days, base 50°F
1,997
Growing degree days, base 55°F
1,325
Growing degree days, base 60°F
783

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,50700
February1,27300
March1,08104
April716024
May4066140
June13548367
July30160595
August54139551
September24532267
October679247
November1,06702
December1,41300

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 13.5 km from Adams County. 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 USW00094038 (Hettinger Muni AP). Public domain.