Oakland climate

Oakland Frost Dates and Growing Season

NOAA 1991-2020 normals for Water Valley, 28.6 km from Oakland, elevation 310 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Water Valley. 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 April 1 and the first fall freeze around November 3, a growing season of about 219 days.

Median at 36°F
last April 13, first October 26
Median at 32°F
last April 1, first November 3
Median at 28°F
last March 16, first November 14

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 29Apr 24Apr 20Apr 16Apr 13Apr 10Apr 6Apr 3Mar 29
32°FApr 18Apr 11Apr 7Apr 4Apr 1Mar 28Mar 23Mar 18Mar 9
28°FApr 4Mar 30Mar 24Mar 19Mar 16Mar 12Mar 6Feb 28Feb 24
24°FMar 20Mar 14Mar 9Mar 5Mar 1Feb 27Feb 23Feb 18Feb 7
20°FMar 9Mar 2Feb 28Feb 23Feb 17Feb 11Feb 3Jan 30Jan 20
16°FMar 1Feb 23Feb 15Feb 7Feb 1Jan 30Jan 23Jan 15Jan 4

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 13Oct 17Oct 21Oct 24Oct 26Oct 28Oct 31Nov 3Nov 7
32°FOct 22Oct 27Oct 30Nov 1Nov 3Nov 6Nov 9Nov 13Nov 20
28°FOct 31Nov 4Nov 7Nov 10Nov 14Nov 19Nov 22Nov 29Dec 4
24°FNov 7Nov 12Nov 17Nov 22Nov 28Dec 1Dec 5Dec 13Dec 25
20°FNov 19Nov 29Dec 4Dec 10Dec 19Dec 25Dec 30Jan 3Jan 13
16°FDec 4Dec 15Dec 25Dec 30Jan 2Jan 6Jan 12Jan 19Feb 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°F217209204199195191187182175
32°F242234229223219214209203195
28°F271261255249244239232226218
24°F303293284277272266259252243
20°F336325316310304298290281270
16°F365357345337332324317309298

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
99% of years
16°F or colder
88% 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
3,127
Cooling degree days, base 65°F
1,881
Growing degree days, base 40°F
8,141
Growing degree days, base 45°F
6,583
Growing degree days, base 50°F
5,173
Growing degree days, base 55°F
3,914
Growing degree days, base 60°F
2,816

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January740139
February568152
March37910174
April16946340
May35177608
June1366816
July0465930
August0459924
September11274712
October14973398
November4197129
December656253

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 28.6 km from Oakland. 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 USC00229400 (Water Valley). Public domain.