Roff climate

Roff Frost Dates and Growing Season

NOAA 1991-2020 normals for Sulphur 4NNE Mesonet, 12.2 km from Roff, elevation 1049 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Sulphur 4NNE Mesonet. 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 4 and the first fall freeze around November 1, a growing season of about 212 days.

Median at 36°F
last April 15, first October 25
Median at 32°F
last April 4, first November 1
Median at 28°F
last March 20, first November 10

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 30Apr 26Apr 22Apr 19Apr 15Apr 12Apr 8Apr 4Mar 30
32°FApr 24Apr 17Apr 11Apr 7Apr 4Mar 31Mar 27Mar 21Mar 15
28°FApr 10Apr 3Mar 30Mar 25Mar 20Mar 15Mar 11Mar 7Feb 28
24°FMar 31Mar 22Mar 15Mar 11Mar 6Mar 3Feb 28Feb 24Feb 14
20°FMar 14Mar 8Mar 3Feb 28Feb 24Feb 19Feb 12Feb 4Jan 29
16°FMar 3Feb 27Feb 19Feb 13Feb 6Jan 31Jan 27Jan 20Jan 6

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 9Oct 15Oct 19Oct 22Oct 25Oct 28Oct 31Nov 3Nov 8
32°FOct 17Oct 22Oct 27Oct 30Nov 1Nov 4Nov 7Nov 12Nov 17
28°FOct 24Oct 31Nov 3Nov 7Nov 10Nov 14Nov 18Nov 23Nov 30
24°FNov 3Nov 9Nov 13Nov 18Nov 23Nov 28Dec 1Dec 5Dec 12
20°FNov 12Nov 20Nov 26Dec 1Dec 3Dec 8Dec 13Dec 19Dec 25
16°FNov 24Dec 1Dec 4Dec 10Dec 16Dec 22Dec 30Jan 6Jan 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°F214206201196192188183177169
32°F238229222217212207201196188
28°F262253247241236230226219209
24°F288279271266260253248242232
20°F317306298292285279273265253
16°F351339332325317309302292281

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
96% 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
3,294
Cooling degree days, base 65°F
1,984
Growing degree days, base 40°F
8,130
Growing degree days, base 45°F
6,601
Growing degree days, base 50°F
5,214
Growing degree days, base 55°F
3,981
Growing degree days, base 60°F
2,904

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January773022
February581362
March39114173
April18242327
May47160579
June0369819
July0516981
August0517982
September15279714
October16875385
November4248137
December713133

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 12.2 km from Roff. 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 USC00348570 (Sulphur 4NNE Mesonet). Public domain.