Big Sandy climate

Big Sandy Frost Dates and Growing Season

NOAA 1991-2020 normals for Gilmer 4 Wnw, 18.9 km from Big Sandy, elevation 390 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Gilmer 4 Wnw. 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 26 and the first fall freeze around November 8, a growing season of about 229 days.

Median at 36°F
last April 9, first November 1
Median at 32°F
last March 26, first November 8
Median at 28°F
last March 9, first November 19

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 26Apr 20Apr 16Apr 12Apr 9Apr 6Apr 2Mar 29Mar 20
32°FApr 16Apr 9Apr 4Mar 31Mar 26Mar 21Mar 15Mar 11Mar 4
28°FApr 1Mar 24Mar 17Mar 13Mar 9Mar 5Mar 1Feb 26Feb 19
24°FMar 16Mar 10Mar 5Feb 28Feb 24Feb 19Feb 10Feb 1Jan 24
20°FMar 6Feb 28Feb 19Feb 9Feb 1Jan 29Jan 22Jan 12Dec 30
16°FFeb 23Feb 9Feb 2Jan 29Jan 22Jan 15Jan 6Dec 31Dec 22

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 23Oct 26Oct 29Nov 1Nov 3Nov 5Nov 9Nov 14
32°FOct 26Oct 31Nov 2Nov 5Nov 8Nov 11Nov 15Nov 19Nov 25
28°FNov 2Nov 6Nov 11Nov 14Nov 19Nov 23Nov 28Dec 2Dec 9
24°FNov 12Nov 18Nov 24Nov 30Dec 2Dec 7Dec 12Dec 18Dec 29
20°FNov 25Dec 1Dec 7Dec 13Dec 21Dec 27Jan 1Jan 8Jan 23
16°FDec 6Dec 14Dec 23Dec 30Jan 2Jan 7Jan 14Jan 27Feb 4

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°F228219214210205201196191183
32°F253245239233229223217212204
28°F280271264259253248243237228
24°F320306297290283276269263253
20°F360345335328319309302293280
16°F365365365362353343334326313

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
92% of years
16°F or colder
61% 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
2,737
Cooling degree days, base 65°F
2,080
Growing degree days, base 40°F
8,636
Growing degree days, base 45°F
7,024
Growing degree days, base 50°F
5,554
Growing degree days, base 55°F
4,234
Growing degree days, base 60°F
3,074

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January649357
February488483
March33417210
April15057366
May28197634
June0387837
July0513978
August0490955
September9303744
October11290448
November36515174
December602469

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 18.9 km from Big Sandy. 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 USC00413546 (Gilmer 4 Wnw). Public domain.