Lake County climate

Lake County Frost Dates and Growing Season

NOAA 1991-2020 normals for Paisley, 16.8 km from Lake County, elevation 4360 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Paisley. 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 June 6 and the first fall freeze around September 14, a growing season of about 98 days.

Median at 32°F
last June 6, first September 14
Median at 28°F
last May 10, first September 28

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°F–––––––––
32°FJun 28Jun 21Jun 15Jun 11Jun 6Jun 1May 28May 19May 12
28°FJun 2May 26May 18May 14May 10May 6May 3Apr 30Apr 25
24°FMay 9May 4May 1Apr 27Apr 23Apr 20Apr 17Apr 13Apr 7
20°FApr 24Apr 18Apr 14Apr 10Apr 6Apr 2Mar 29Mar 23Mar 13
16°FApr 8Apr 1Mar 26Mar 18Mar 13Mar 7Mar 2Feb 24Feb 15

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°F–––––––––
32°FAug 27Sep 2Sep 7Sep 11Sep 14Sep 18Sep 21Sep 24Sep 28
28°FSep 12Sep 18Sep 22Sep 25Sep 28Oct 1Oct 4Oct 7Oct 13
24°FSep 26Oct 1Oct 4Oct 7Oct 10Oct 13Oct 17Oct 20Oct 27
20°FOct 8Oct 12Oct 15Oct 18Oct 22Oct 26Oct 30Nov 4Nov 11
16°FOct 15Oct 20Oct 25Oct 29Nov 2Nov 6Nov 11Nov 19Nov 25

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°F928276716659524538
32°F1261161091039892867969
28°F161154148143138133127119111
24°F193184177173169164159152145
20°F228217210204198193187181173
16°F267255246240233226220211202

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
6,508
Cooling degree days, base 65°F
244
Growing degree days, base 40°F
3,864
Growing degree days, base 45°F
2,754
Growing degree days, base 50°F
1,860
Growing degree days, base 55°F
1,148
Growing degree days, base 60°F
607

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,00900
February82701
March76306
April602032
May3773148
June19223291
July44113535
August6084490
September20619279
October530172
November82707
December1,07200

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 16.8 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 USC00356426 (Paisley). Public domain.