Lyons climate

Lyons Frost Dates and Growing Season

NOAA 1991-2020 normals for Metter, 32.5 km from Lyons, elevation 120 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Metter. 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 2 and the first fall freeze around November 27, a growing season of about 269 days.

Median at 36°F
last March 19, first November 13
Median at 32°F
last March 2, first November 27
Median at 28°F
last February 12, first December 16

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 7Mar 31Mar 27Mar 23Mar 19Mar 15Mar 10Mar 4Feb 27
32°FMar 25Mar 17Mar 11Mar 6Mar 2Feb 27Feb 21Feb 13Feb 2
28°FMar 12Mar 4Feb 28Feb 19Feb 12Feb 6Feb 1Jan 25Jan 14
24°FMar 2Feb 19Feb 9Feb 2Jan 28Jan 21Jan 14Jan 7Dec 29
20°FFeb 19Feb 5Jan 29Jan 24Jan 19Jan 13Jan 7Dec 31Dec 22
16°F–––––––––

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°FNov 1Nov 4Nov 7Nov 10Nov 13Nov 17Nov 21Nov 27Dec 5
32°FNov 7Nov 12Nov 18Nov 22Nov 27Dec 2Dec 6Dec 15Dec 28
28°FNov 17Nov 26Dec 3Dec 8Dec 16Dec 24Jan 1Jan 7Jan 14
24°FDec 3Dec 10Dec 20Dec 28Jan 3Jan 7Jan 12Jan 19Feb 2
20°FDec 11Dec 24Dec 31Jan 6Jan 11Jan 15Jan 19Jan 27Feb 10
16°F–––––––––

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°F267259252247241236231223216
32°F306293284277269263257249240
28°F342332322312305298291280267
24°F365365354345338332324312300
20°F365365365365365365353341328
16°F365365365365365365365365365

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
97% of years
24°F or colder
78% of years
20°F or colder
39% of years
16°F or colder
10% 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
1,793
Cooling degree days, base 65°F
2,475
Growing degree days, base 40°F
9,845
Growing degree days, base 45°F
8,103
Growing degree days, base 50°F
6,467
Growing degree days, base 55°F
4,967
Growing degree days, base 60°F
3,627

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4814109
February3359152
March20434313
April6595482
May5292752
June0453903
July05411,006
August0522987
September1364813
October54131544
November23723259
December4108149

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 32.5 km from Lyons. 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 USC00095811 (Metter). Public domain.