Camas climate

Camas Frost Dates and Growing Season

NOAA 1991-2020 normals for Troutdale, 3.8 km from Camas, elevation 33 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Troutdale. 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 March 26 and the first fall freeze around November 17, a growing season of about 237 days.

Median at 36°F
last April 24, first October 30
Median at 32°F
last March 26, first November 17
Median at 28°F
last February 22, first December 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°FMay 9May 3Apr 30Apr 27Apr 24Apr 20Apr 17Apr 11Apr 3
32°FApr 21Apr 12Apr 5Mar 31Mar 26Mar 21Mar 14Mar 5Feb 27
28°FMar 21Mar 10Mar 3Feb 27Feb 22Feb 17Feb 10Jan 31Jan 15
24°FFeb 23Feb 16Feb 11Feb 2Jan 28Jan 19Jan 11Jan 2Dec 18
20°FFeb 20Feb 11Feb 1Jan 26Jan 19Jan 13Jan 7Dec 30Dec 14
16°FFeb 4Jan 30Jan 24Jan 18Jan 14Jan 11Jan 6Jan 1Dec 24

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°FOct 11Oct 17Oct 22Oct 25Oct 30Nov 3Nov 9Nov 13Nov 21
32°FOct 26Nov 1Nov 8Nov 13Nov 17Nov 22Nov 28Dec 3Dec 10
28°FNov 14Nov 21Nov 28Dec 2Dec 7Dec 12Dec 21Dec 30Jan 11
24°FNov 28Dec 5Dec 10Dec 18Dec 28Jan 3Jan 10Jan 22Feb 6
20°FDec 5Dec 16Dec 25Jan 1Jan 6Jan 14Jan 20Feb 1Feb 14
16°FDec 14Dec 26Jan 3Jan 7Jan 12Jan 16Jan 19Jan 27Feb 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°F220209201196189183178172164
32°F272261252245237229222213202
28°F336319309300292283275265252
24°F365365359349339330321312303
20°F365365365365365363352338323
16°F365365365365365365365365350

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
99% of years
24°F or colder
74% of years
20°F or colder
43% of years
16°F or colder
22% 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
4,574
Cooling degree days, base 65°F
361
Growing degree days, base 40°F
5,114
Growing degree days, base 45°F
3,641
Growing degree days, base 50°F
2,453
Growing degree days, base 55°F
1,530
Growing degree days, base 60°F
832

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January78102
February63005
March566025
April415183
May23916248
June11640374
July26126566
August23130572
September9846398
October3363155
November575023
December77003

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 3.8 km from Camas. 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 USC00358634 (Troutdale). Public domain.