Anderson climate

Anderson Frost Dates and Growing Season

NOAA 1991-2020 normals for Washington SP, 24.6 km from Anderson, elevation 215 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Washington SP. 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 7 and the first fall freeze around November 19, a growing season of about 259 days.

Median at 36°F
last March 22, first November 7
Median at 32°F
last March 7, first November 19
Median at 28°F
last February 19, first December 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°FApr 15Apr 7Apr 1Mar 27Mar 22Mar 17Mar 12Mar 7Feb 28
32°FMar 31Mar 22Mar 16Mar 11Mar 7Mar 2Feb 27Feb 21Feb 10
28°FMar 16Mar 8Mar 2Feb 25Feb 19Feb 13Feb 5Jan 29Jan 19
24°FMar 5Feb 23Feb 15Feb 6Jan 31Jan 25Jan 17Jan 9Dec 31
20°FFeb 15Feb 5Jan 29Jan 23Jan 16Jan 11Jan 6Jan 1Dec 21
16°FFeb 3Jan 22Jan 14Jan 11Jan 7Jan 4Jan 2Dec 30Dec 21

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 24Oct 29Nov 1Nov 4Nov 7Nov 11Nov 15Nov 20Nov 27
32°FNov 1Nov 5Nov 10Nov 14Nov 19Nov 23Nov 28Dec 4Dec 11
28°FNov 11Nov 18Nov 24Nov 29Dec 3Dec 9Dec 18Dec 29Jan 5
24°FNov 23Dec 2Dec 9Dec 17Dec 28Jan 2Jan 7Jan 18Feb 1
20°FDec 7Dec 20Dec 29Jan 1Jan 4Jan 9Jan 14Jan 24Feb 5
16°FDec 19Dec 28Jan 1Jan 2Jan 4Jan 8Jan 12Jan 17Feb 1

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°F261252245239233228221214204
32°F291279271264259252245238229
28°F333318307299291283276267255
24°F365358346337330319310302287
20°F365365365365365358350341327
16°F365365365365365365365365357

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
99% of years
24°F or colder
86% of years
20°F or colder
46% of years
16°F or colder
15% 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
1,750
Cooling degree days, base 65°F
2,864
Growing degree days, base 40°F
10,287
Growing degree days, base 45°F
8,553
Growing degree days, base 50°F
6,917
Growing degree days, base 55°F
5,412
Growing degree days, base 60°F
4,055

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4779117
February32715172
March18154357
April62130519
May6319778
June0485934
July05841,049
August06061,071
September2419867
October52182597
November22447303
December41914154

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 24.6 km from Anderson. 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 USC00419491 (Washington SP). Public domain.