Sanderson climate

Sanderson Frost Dates and Growing Season

NOAA 1991-2020 normals for Sanderson, 0.2 km from Sanderson, elevation 2788 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Sanderson. 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 11 and the first fall freeze around November 11, a growing season of about 243 days.

Median at 36°F
last March 31, first November 3
Median at 32°F
last March 11, first November 11
Median at 28°F
last February 28, first November 23

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 20Apr 12Apr 7Apr 3Mar 31Mar 25Mar 20Mar 13Mar 7
32°FApr 6Mar 29Mar 22Mar 15Mar 11Mar 7Mar 3Feb 27Feb 20
28°FMar 19Mar 12Mar 8Mar 3Feb 28Feb 23Feb 18Feb 13Feb 5
24°FMar 9Mar 1Feb 23Feb 17Feb 11Feb 6Jan 31Jan 22Jan 13
20°FFeb 27Feb 12Feb 4Jan 28Jan 21Jan 15Jan 7Dec 31Dec 20
16°FFeb 13Jan 29Jan 21Jan 13Jan 7Jan 3Dec 31Dec 23Dec 14

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 20Oct 24Oct 28Oct 31Nov 3Nov 5Nov 8Nov 12Nov 15
32°FOct 28Nov 1Nov 5Nov 8Nov 11Nov 14Nov 17Nov 22Nov 27
28°FNov 7Nov 11Nov 15Nov 19Nov 23Nov 27Nov 30Dec 4Dec 10
24°FNov 16Nov 22Nov 28Dec 1Dec 6Dec 10Dec 16Dec 22Jan 1
20°FNov 29Dec 6Dec 11Dec 18Dec 23Dec 29Jan 4Jan 13Jan 27
16°FDec 10Dec 18Dec 23Dec 30Jan 2Jan 6Jan 14Jan 22Feb 5

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°F242234227221216210205199190
32°F269260254249243237231223213
28°F296285278272267261256249240
24°F331321313305298291284276265
20°F365362353345338331322311299
16°F365365365365365365359348337

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
85% of years
16°F or colder
41% 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
2,151
Cooling degree days, base 65°F
2,476
Growing degree days, base 40°F
9,517
Growing degree days, base 45°F
7,810
Growing degree days, base 50°F
6,230
Growing degree days, base 55°F
4,812
Growing degree days, base 60°F
3,561

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January558056
February3783116
March21330305
April68119504
May9327783
June0494943
July0527992
August0530995
September6326770
October74111507
November30611198
December539062

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 0.2 km from Sanderson. 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 USC00418022 (Sanderson). Public domain.