Buellton climate

Buellton Frost Dates and Growing Season

NOAA 1991-2020 normals for Cachuma Lake, 19.7 km from Buellton, elevation 789 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cachuma 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 April 11 and the first fall freeze around November 8, a growing season of about 209 days.

Median at 36°F
last May 12, first October 17
Median at 32°F
last April 11, first November 8
Median at 28°F
last February 27, first November 27

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 7May 30May 25May 18May 12May 5Apr 30Apr 25Apr 19
32°FMay 6Apr 26Apr 20Apr 16Apr 11Apr 7Apr 3Mar 29Mar 14
28°FApr 4Mar 25Mar 12Mar 4Feb 27Feb 22Feb 15Feb 6Jan 24
24°FFeb 25Feb 13Feb 5Jan 31Jan 24Jan 13Jan 5Dec 29Dec 17
20°FFeb 2Jan 24Jan 14Jan 8Jan 2Dec 30Dec 23Dec 17Dec 9
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°FSep 21Sep 30Oct 5Oct 12Oct 17Oct 22Oct 25Oct 30Nov 4
32°FOct 14Oct 25Nov 1Nov 4Nov 8Nov 12Nov 17Nov 22Nov 29
28°FNov 7Nov 14Nov 19Nov 23Nov 27Dec 1Dec 4Dec 10Dec 17
24°FNov 22Nov 30Dec 4Dec 9Dec 13Dec 18Dec 25Jan 2Jan 20
20°FDec 4Dec 9Dec 16Dec 20Dec 26Dec 31Jan 4Jan 11Jan 22
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°F188175167160154147139130119
32°F245230222215209202195186171
28°F312298288280271263256246232
24°F363352343336328320312303288
20°F365365365365365364357347334
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
100% of years
24°F or colder
88% of years
20°F or colder
35% of years
16°F or colder
5% 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
2,432
Cooling degree days, base 65°F
657
Growing degree days, base 40°F
7,355
Growing degree days, base 45°F
5,568
Growing degree days, base 50°F
3,910
Growing degree days, base 55°F
2,504
Growing degree days, base 60°F
1,420

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January443078
February372190
March3272162
April2349233
May14329351
June4972473
July7160618
August4185646
September21131560
October10058423
November26911208
December462069

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 19.7 km from Buellton. 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 USC00041253 (Cachuma Lake). Public domain.