Woods Bay climate

Woods Bay Frost Dates and Growing Season

NOAA 1991-2020 normals for Bigfork 13 S, 14 km from Woods Bay, elevation 2979 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bigfork 13 S. 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 1 and the first fall freeze around October 15, a growing season of about 165 days.

Median at 36°F
last May 16, first October 3
Median at 32°F
last May 1, first October 15
Median at 28°F
last April 11, first October 30

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 5May 28May 23May 19May 16May 13May 11May 8May 4
32°FMay 16May 9May 5May 3May 1Apr 29Apr 26Apr 22Apr 16
28°FApr 28Apr 22Apr 18Apr 14Apr 11Apr 7Apr 4Apr 1Mar 25
24°FApr 9Apr 4Mar 31Mar 27Mar 23Mar 18Mar 13Mar 8Mar 3
20°FMar 29Mar 22Mar 16Mar 12Mar 8Mar 3Feb 28Feb 23Feb 15
16°FMar 22Mar 14Mar 9Mar 4Mar 1Feb 24Feb 18Feb 7Jan 23

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 20Sep 25Sep 29Oct 1Oct 3Oct 5Oct 7Oct 11Oct 15
32°FSep 30Oct 4Oct 8Oct 12Oct 15Oct 18Oct 20Oct 25Oct 30
28°FOct 11Oct 18Oct 22Oct 27Oct 30Nov 1Nov 5Nov 10Nov 18
24°FOct 21Oct 30Nov 3Nov 7Nov 10Nov 14Nov 19Nov 24Nov 30
20°FNov 1Nov 8Nov 12Nov 18Nov 23Nov 26Dec 1Dec 6Dec 15
16°FNov 9Nov 18Nov 24Nov 28Dec 3Dec 7Dec 15Dec 22Jan 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°F156150146142138134129123114
32°F186179173170165161157152144
28°F225216210205200195190183174
24°F261250243237232227220214205
20°F289276269262256250243236227
16°F315302293283276269262255242

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
6,877
Cooling degree days, base 65°F
249
Growing degree days, base 40°F
3,702
Growing degree days, base 45°F
2,657
Growing degree days, base 50°F
1,807
Growing degree days, base 55°F
1,117
Growing degree days, base 60°F
597

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,09900
February94600
March85401
April624015
May3722136
June18219290
July40119544
August44100521
September21710253
October570044
November84504
December1,08300

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 14 km from Woods Bay. 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 USC00240755 (Bigfork 13 S). Public domain.