Adams climate

Adams Frost Dates and Growing Season

NOAA 1991-2020 normals for Virginia, 23.9 km from Adams, elevation 1545 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Virginia. 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 20, a growing season of about 179 days.

Median at 36°F
last May 2, first October 10
Median at 32°F
last April 22, first October 20
Median at 28°F
last April 11, 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 12May 9May 6May 4May 2Apr 30Apr 26Apr 22Apr 17
32°FMay 5May 1Apr 29Apr 24Apr 22Apr 18Apr 16Apr 11Apr 6
28°FApr 27Apr 21Apr 17Apr 14Apr 11Apr 7Apr 4Apr 1Mar 27
24°FApr 16Apr 11Apr 6Apr 3Mar 31Mar 29Mar 25Mar 19Mar 13
20°FApr 6Apr 1Mar 30Mar 26Mar 22Mar 17Mar 14Mar 9Mar 4
16°FMar 30Mar 24Mar 19Mar 15Mar 12Mar 9Mar 5Mar 2Feb 25

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 26Oct 1Oct 4Oct 8Oct 10Oct 13Oct 16Oct 19Oct 23
32°FOct 1Oct 9Oct 14Oct 17Oct 20Oct 23Oct 25Oct 28Nov 1
28°FOct 14Oct 21Oct 24Oct 28Oct 31Nov 1Nov 4Nov 7Nov 12
24°FOct 25Oct 30Nov 1Nov 4Nov 6Nov 9Nov 12Nov 16Nov 22
20°FOct 31Nov 4Nov 7Nov 11Nov 14Nov 17Nov 21Nov 27Dec 2
16°FNov 7Nov 12Nov 16Nov 20Nov 24Nov 28Dec 1Dec 5Dec 12

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°F180173169164160157153149143
32°F201193188184179175170165157
28°F222214210205201197192187178
24°F243235229225220216211207198
20°F262253248242238233228223215
16°F282272266261257252247240231

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
6,042
Cooling degree days, base 65°F
1,054
Growing degree days, base 40°F
5,675
Growing degree days, base 45°F
4,500
Growing degree days, base 50°F
3,450
Growing degree days, base 55°F
2,522
Growing degree days, base 60°F
1,721

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26300
February1,01603
March783137
April4368135
May17653351
June20215645
July2343806
August5293753
September88124490
October36617195
November761133
December1,12502

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 23.9 km from Adams. 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 USC00258875 (Virginia). Public domain.