Lake County climate

Lake County Frost Dates and Growing Season

NOAA 1991-2020 normals for Wellston 1N, 29.4 km from Lake County, elevation 773 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Wellston 1N. 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 May 28 and the first fall freeze around September 25, a growing season of about 119 days.

Median at 36°F
last June 9, first September 14
Median at 32°F
last May 28, first September 25
Median at 28°F
last May 18, first October 8

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°FJul 2Jun 22Jun 16Jun 12Jun 9Jun 5Jun 2May 30May 25
32°FJun 13Jun 7Jun 3May 31May 28May 25May 23May 19May 13
28°FJun 1May 28May 24May 21May 18May 15May 10May 6Apr 29
24°FMay 23May 20May 14May 9May 5May 1Apr 29Apr 24Apr 18
20°FMay 14May 5May 1Apr 27Apr 23Apr 19Apr 16Apr 11Apr 5
16°FApr 29Apr 22Apr 17Apr 13Apr 9Apr 5Apr 2Mar 31Mar 25

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°FAug 26Sep 1Sep 6Sep 11Sep 14Sep 17Sep 20Sep 23Sep 28
32°FSep 8Sep 16Sep 20Sep 23Sep 25Sep 28Oct 1Oct 4Oct 10
28°FSep 22Sep 28Oct 2Oct 5Oct 8Oct 11Oct 15Oct 19Oct 25
24°FOct 7Oct 13Oct 17Oct 20Oct 24Oct 28Oct 31Nov 2Nov 6
20°FOct 20Oct 27Oct 31Nov 2Nov 4Nov 7Nov 10Nov 13Nov 19
16°FNov 2Nov 6Nov 10Nov 12Nov 15Nov 18Nov 22Nov 27Dec 1

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°F1171101051009589837766
32°F13913212712311911511110496
28°F168160153149144139134129120
24°F192184179174169165161154147
20°F216209203198194189184178171
16°F243234228224219215210204196

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
7,893
Cooling degree days, base 65°F
342
Growing degree days, base 40°F
3,848
Growing degree days, base 45°F
2,887
Growing degree days, base 50°F
2,054
Growing degree days, base 55°F
1,336
Growing degree days, base 60°F
755

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,39300
February1,21500
March1,08709
April698139
May36018193
June10969414
July47119538
August6296499
September22236285
October575370
November89907
December1,22800

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 29.4 km from Lake County. 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 USC00208774 (Wellston 1N). Public domain.