Gray climate

Gray Frost Dates and Growing Season

NOAA 1991-2020 normals for Gray, 6.3 km from Gray, elevation 378 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Gray. 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 April 28 and the first fall freeze around October 19, a growing season of about 172 days.

Median at 36°F
last May 9, first October 5
Median at 32°F
last April 28, first October 19
Median at 28°F
last April 15, first November 1

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 24May 18May 15May 11May 9May 6May 3May 1Apr 28
32°FMay 10May 6May 2Apr 30Apr 28Apr 26Apr 23Apr 20Apr 15
28°FApr 28Apr 23Apr 20Apr 18Apr 15Apr 12Apr 10Apr 7Apr 3
24°FApr 17Apr 12Apr 9Apr 6Apr 4Apr 2Mar 31Mar 28Mar 21
20°FApr 6Apr 3Apr 1Mar 30Mar 26Mar 23Mar 19Mar 16Mar 12
16°FApr 1Mar 27Mar 24Mar 20Mar 17Mar 14Mar 12Mar 9Mar 5

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 25Sep 29Oct 1Oct 3Oct 5Oct 8Oct 11Oct 15Oct 19
32°FOct 5Oct 9Oct 12Oct 16Oct 19Oct 22Oct 26Oct 30Nov 4
28°FOct 17Oct 22Oct 26Oct 29Nov 1Nov 3Nov 6Nov 10Nov 15
24°FNov 1Nov 4Nov 8Nov 11Nov 13Nov 16Nov 19Nov 23Nov 27
20°FNov 11Nov 15Nov 18Nov 21Nov 24Nov 27Nov 30Dec 2Dec 6
16°FNov 19Nov 24Nov 28Dec 1Dec 2Dec 5Dec 8Dec 12Dec 17

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°F166160156152149146142138132
32°F191184180176172169165160153
28°F217211206202198195192187180
24°F242235231227223220216211205
20°F262255251248243239235230223
16°F279273268264260257253248242

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
7,163
Cooling degree days, base 65°F
396
Growing degree days, base 40°F
4,153
Growing degree days, base 45°F
3,111
Growing degree days, base 50°F
2,212
Growing degree days, base 55°F
1,459
Growing degree days, base 60°F
852

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,33300
February1,12700
March99405
April647128
May3469165
June10361410
July15156606
August21131575
September15837333
October490281
November788011
December1,14201

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 6.3 km from Gray. 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 USC00173295 (Gray). Public domain.