Oconee County climate

Oconee County Frost Dates and Growing Season

NOAA 1991-2020 normals for U Of Ga Plt Sci, 10 km from Oconee County, elevation 840 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for U Of Ga Plt Sci. 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 March 27 and the first fall freeze around November 8, a growing season of about 228 days.

Median at 36°F
last April 7, first October 29
Median at 32°F
last March 27, first November 8
Median at 28°F
last March 12, first November 22

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°FApr 22Apr 17Apr 14Apr 11Apr 7Apr 4Apr 1Mar 29Mar 23
32°FApr 12Apr 7Apr 3Mar 31Mar 27Mar 23Mar 18Mar 14Mar 5
28°FMar 31Mar 25Mar 19Mar 16Mar 12Mar 7Mar 2Feb 25Feb 17
24°FMar 19Mar 14Mar 6Mar 1Feb 25Feb 18Feb 11Feb 3Jan 25
20°FMar 6Feb 27Feb 19Feb 10Feb 4Jan 31Jan 25Jan 17Jan 7
16°FFeb 24Feb 11Feb 3Jan 31Jan 25Jan 19Jan 12Jan 6Dec 29

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°FOct 18Oct 22Oct 24Oct 27Oct 29Nov 1Nov 3Nov 6Nov 12
32°FOct 26Oct 31Nov 1Nov 5Nov 8Nov 11Nov 15Nov 21Nov 29
28°FNov 4Nov 9Nov 13Nov 17Nov 22Nov 27Dec 1Dec 7Dec 16
24°FNov 14Nov 23Nov 29Dec 4Dec 8Dec 14Dec 22Dec 29Jan 8
20°FNov 30Dec 8Dec 17Dec 24Dec 29Jan 3Jan 8Jan 14Jan 25
16°FDec 12Dec 23Dec 29Jan 3Jan 8Jan 12Jan 17Jan 25Feb 3

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°F226217211207203199196191184
32°F256247240233228223218212205
28°F288278270263256251245238228
24°F325312304297290283276266257
20°F353344336330323315307298284
16°F365365365356348341334327313

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
94% of years
16°F or colder
70% 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
2,999
Cooling degree days, base 65°F
1,718
Growing degree days, base 40°F
8,009
Growing degree days, base 45°F
6,417
Growing degree days, base 50°F
4,994
Growing degree days, base 55°F
3,733
Growing degree days, base 60°F
2,641

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January696033
February541045
March3888162
April17439326
May36164594
June2346795
July0453917
August0409874
September10239679
October13852387
November3976132
December619150

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 10 km from Oconee 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 USC00098950 (U Of Ga Plt Sci). Public domain.