Leon climate

Leon Frost Dates and Growing Season

NOAA 1991-2020 normals for Leon 6 Ese, 8.8 km from Leon, elevation 1000 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Leon 6 Ese. 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 30 and the first fall freeze around October 8, a growing season of about 161 days.

Median at 36°F
last May 9, first September 29
Median at 32°F
last April 30, first October 8
Median at 28°F
last April 19, first October 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°FMay 24May 20May 16May 12May 9May 6May 3Apr 30Apr 24
32°FMay 15May 11May 6May 3Apr 30Apr 28Apr 24Apr 20Apr 16
28°FMay 4Apr 30Apr 26Apr 22Apr 19Apr 16Apr 12Apr 9Apr 3
24°FApr 23Apr 17Apr 13Apr 10Apr 7Apr 4Apr 1Mar 29Mar 23
20°FApr 13Apr 7Apr 4Apr 1Mar 30Mar 25Mar 22Mar 17Mar 10
16°FApr 3Mar 30Mar 24Mar 21Mar 17Mar 13Mar 10Mar 5Mar 1

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 17Sep 20Sep 23Sep 26Sep 29Oct 1Oct 3Oct 7Oct 12
32°FSep 26Sep 30Oct 2Oct 5Oct 8Oct 12Oct 14Oct 17Oct 22
28°FOct 4Oct 10Oct 14Oct 17Oct 19Oct 22Oct 25Oct 28Nov 1
24°FOct 16Oct 21Oct 24Oct 27Oct 29Nov 1Nov 3Nov 7Nov 12
20°FOct 26Oct 31Nov 2Nov 5Nov 7Nov 10Nov 13Nov 18Nov 24
16°FNov 2Nov 7Nov 10Nov 14Nov 18Nov 22Nov 26Dec 1Dec 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°F162155150147143139135131124
32°F182175170165161157153149141
28°F202195191188183179174170163
24°F224217212208204200196191184
20°F249238233228224220215209200
16°F270261254249245239234229220

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
6,406
Cooling degree days, base 65°F
823
Growing degree days, base 40°F
5,231
Growing degree days, base 45°F
4,091
Growing degree days, base 50°F
3,078
Growing degree days, base 55°F
2,189
Growing degree days, base 60°F
1,434

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,31300
February1,07402
March817239
April4666113
May20048326
June29169590
July3287749
August11229683
September12773401
October42811147
November785025
December1,15502

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 8.8 km from Leon. 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 USC00134758 (Leon 6 Ese). Public domain.