Augusta climate

Augusta Frost Dates and Growing Season

NOAA 1991-2020 normals for Augusta RS, 1.3 km from Augusta, elevation 960 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Augusta RS. 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 7 and the first fall freeze around October 1, a growing season of about 146 days.

Median at 36°F
last May 17, first September 24
Median at 32°F
last May 7, first October 1
Median at 28°F
last April 26, first October 11

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

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 16Sep 19Sep 21Sep 24Sep 26Sep 29Oct 2Oct 5
32°FSep 17Sep 22Sep 26Sep 28Oct 1Oct 4Oct 7Oct 10Oct 14
28°FSep 25Oct 1Oct 4Oct 7Oct 11Oct 14Oct 17Oct 21Oct 26
24°FOct 6Oct 12Oct 16Oct 20Oct 23Oct 26Oct 29Nov 1Nov 5
20°FOct 18Oct 24Oct 28Oct 31Nov 2Nov 4Nov 7Nov 12Nov 17
16°FOct 31Nov 2Nov 6Nov 10Nov 13Nov 16Nov 20Nov 23Nov 28

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°F147141137133129126121116110
32°F165158154150146143139134128
28°F186179174169166161157152144
24°F208202197192188183178173165
20°F228222217212209204200195188
16°F246239234230226222218213205

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
8,313
Cooling degree days, base 65°F
475
Growing degree days, base 40°F
4,182
Growing degree days, base 45°F
3,203
Growing degree days, base 50°F
2,339
Growing degree days, base 55°F
1,588
Growing degree days, base 60°F
958

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,61200
February1,35600
March1,102010
April645147
May28924237
June59101492
July17180627
August40128553
September20939300
October595367
November98004
December1,41000

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 1.3 km from Augusta. 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 USC00470382 (Augusta RS). Public domain.