Loon Lake climate

Loon Lake Frost Dates and Growing Season

NOAA 1991-2020 normals for Deer Park AP, 18.1 km from Loon Lake, elevation 2191 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Deer Park AP. 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 22 and the first fall freeze around September 14, a growing season of about 112 days.

Median at 32°F
last May 22, first September 14
Median at 28°F
last May 3, first September 29

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 15Jun 5May 31May 27May 22May 17May 13May 8May 2
28°FMay 21May 14May 11May 6May 3Apr 30Apr 28Apr 23Apr 18
24°FMay 7May 1Apr 27Apr 22Apr 19Apr 14Apr 7Mar 31Mar 24
20°FApr 20Apr 9Apr 3Mar 29Mar 24Mar 19Mar 14Mar 10Mar 5
16°FMar 24Mar 16Mar 12Mar 8Mar 6Mar 3Feb 28Feb 24Feb 16

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 28Sep 3Sep 7Sep 10Sep 14Sep 18Sep 21Sep 25Oct 1
28°FSep 14Sep 19Sep 23Sep 27Sep 29Oct 1Oct 4Oct 7Oct 14
24°FSep 27Oct 1Oct 3Oct 6Oct 10Oct 15Oct 20Oct 25Nov 3
20°FOct 5Oct 12Oct 17Oct 23Oct 27Oct 31Nov 5Nov 11Nov 20
16°FOct 18Oct 26Oct 31Nov 4Nov 10Nov 14Nov 20Nov 25Dec 2

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°F989083787267605242
32°F1401301231171121081029484
28°F170162155150146140135129122
24°F209199192184178173165158150
20°F245237230223216209201193181
16°F278268260254247242236229219

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
7,286
Cooling degree days, base 65°F
217
Growing degree days, base 40°F
3,505
Growing degree days, base 45°F
2,509
Growing degree days, base 50°F
1,685
Growing degree days, base 55°F
1,021
Growing degree days, base 60°F
531

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,16300
February97400
March85101
April609026
May3674146
June21218262
July5999505
August6681481
September25614228
October632035
November92601
December1,17200

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 18.1 km from Loon Lake. 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 USW00094119 (Deer Park AP). Public domain.