Timber Lake climate

Timber Lake Frost Dates and Growing Season

NOAA 1991-2020 normals for Timber Lake, 0.2 km from Timber Lake, elevation 2173 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Timber Lake. 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 10 and the first fall freeze around September 30, a growing season of about 141 days.

Median at 36°F
last May 19, first September 22
Median at 32°F
last May 10, first September 30
Median at 28°F
last April 30, first October 7

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°FJun 2May 29May 25May 23May 19May 17May 14May 11May 7
32°FMay 23May 18May 15May 12May 10May 8May 5May 2Apr 29
28°FMay 12May 8May 5May 2Apr 30Apr 27Apr 25Apr 21Apr 15
24°FMay 4Apr 30Apr 26Apr 23Apr 20Apr 17Apr 13Apr 10Apr 4
20°FApr 24Apr 20Apr 16Apr 13Apr 10Apr 8Apr 4Apr 1Mar 27
16°FApr 16Apr 11Apr 8Apr 5Apr 2Mar 31Mar 27Mar 22Mar 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°FSep 10Sep 14Sep 18Sep 20Sep 22Sep 24Sep 27Sep 29Oct 4
32°FSep 17Sep 21Sep 25Sep 28Sep 30Oct 2Oct 4Oct 8Oct 13
28°FSep 22Sep 28Oct 1Oct 4Oct 7Oct 10Oct 13Oct 16Oct 20
24°FOct 2Oct 6Oct 10Oct 14Oct 17Oct 20Oct 22Oct 26Oct 30
20°FOct 10Oct 15Oct 19Oct 23Oct 26Oct 29Nov 1Nov 4Nov 9
16°FOct 19Oct 25Oct 28Nov 1Nov 3Nov 6Nov 9Nov 13Nov 18

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°F141135132129125122117113108
32°F161154149145141137134129123
28°F178171167163159155151146138
24°F198191186182179174170165159
20°F219212206201198193188183177
16°F237229223218215210205201194

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
7,821
Cooling degree days, base 65°F
666
Growing degree days, base 40°F
4,535
Growing degree days, base 45°F
3,517
Growing degree days, base 50°F
2,619
Growing degree days, base 55°F
1,842
Growing degree days, base 60°F
1,187

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,49100
February1,23900
March1,00609
April607157
May29220234
June65104490
July14251702
August21216660
September15770376
October573484
November98606
December1,37200

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 0.2 km from Timber 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 USC00398307 (Timber Lake). Public domain.