Cloverdale climate

Cloverdale Frost Dates and Growing Season

NOAA 1991-2020 normals for Cloverdale, 1.6 km from Cloverdale, elevation 400 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cloverdale. 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 February 25 and the first fall freeze around December 3, a growing season of about 279 days.

Median at 36°F
last April 5, first November 14
Median at 32°F
last February 25, first December 3
Median at 28°F
last January 12, first December 19

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°FApr 27Apr 19Apr 15Apr 9Apr 5Mar 31Mar 27Mar 16Mar 4
32°FApr 2Mar 24Mar 10Mar 2Feb 25Feb 17Feb 8Jan 29Jan 18
28°FFeb 21Feb 5Jan 28Jan 19Jan 12Jan 6Jan 1Dec 27Dec 20
24°FJan 23Jan 14Jan 8Jan 3Dec 31Dec 28Dec 21Dec 17Dec 8
20°F–––––––––
16°F–––––––––

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 29Nov 2Nov 7Nov 11Nov 14Nov 18Nov 22Nov 27Dec 2
32°FNov 14Nov 20Nov 26Nov 30Dec 3Dec 6Dec 11Dec 16Dec 25
28°FNov 27Dec 3Dec 9Dec 13Dec 19Dec 24Dec 31Jan 5Jan 18
24°FDec 2Dec 11Dec 17Dec 22Dec 27Dec 31Jan 4Jan 9Jan 20
20°F–––––––––
16°F–––––––––

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°F257245237229222216209201192
32°F322307298289279271262250235
28°F365362354348341334326318302
24°F365365365365365365365359347
20°F365365365365365365365365365
16°F365365365365365365365365365

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
82% of years
24°F or colder
28% of years
20°F or colder
4% of years
16°F or colder
0% 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
2,378
Cooling degree days, base 65°F
1,210
Growing degree days, base 40°F
7,962
Growing degree days, base 45°F
6,185
Growing degree days, base 50°F
4,557
Growing degree days, base 55°F
3,195
Growing degree days, base 60°F
2,087

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January495044
February370090
March3075182
April19122284
May7192486
June12219657
July1304769
August1279743
September9210651
October8476458
November3184158
December521036

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 1.6 km from Cloverdale. 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 USC00041838 (Cloverdale). Public domain.