Pescadero climate

Pescadero Frost Dates and Growing Season

NOAA 1991-2020 normals for San Gregorio 2 Se, 6.5 km from Pescadero, elevation 275 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for San Gregorio 2 Se. 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 2 and the first fall freeze around November 25, a growing season of about 268 days.

Median at 36°F
last April 26, first November 1
Median at 32°F
last March 2, first November 25
Median at 28°F
last January 2, first December 12

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 24May 8May 1Apr 26Apr 19Apr 12Apr 3Mar 26
32°FApr 15Apr 1Mar 26Mar 13Mar 2Feb 20Feb 6Jan 25Dec 31
28°FFeb 19Feb 2Jan 24Jan 12Jan 2Dec 27Dec 20Dec 10Dec 1
24°FJan 10Jan 1Dec 30Dec 27Dec 19Dec 12Dec 9Dec 7Dec 5
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 2Oct 12Oct 20Oct 29Nov 1Nov 5Nov 10Nov 15Nov 24
32°FNov 1Nov 8Nov 14Nov 19Nov 25Nov 30Dec 5Dec 16Jan 1
28°FNov 21Nov 28Dec 3Dec 6Dec 12Dec 20Dec 28Jan 6Jan 26
24°FDec 2Dec 4Dec 6Dec 9Dec 12Dec 18Dec 27Dec 30Jan 5
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°F222210202195187178169158144
32°F326307294282268258246234218
28°F365365365364351340334324309
24°F365365365365365365365365357
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
99% of years
28°F or colder
61% of years
24°F or colder
11% of years
20°F or colder
0% 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
3,722
Cooling degree days, base 65°F
23
Growing degree days, base 40°F
5,428
Growing degree days, base 45°F
3,629
Growing degree days, base 50°F
2,010
Growing degree days, base 55°F
828
Growing degree days, base 60°F
194

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January465055
February398060
March423074
April371093
May3091161
June2332219
July1444326
August1264343
September1407317
October2544218
November380098
December479048

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 6.5 km from Pescadero. 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 USC00047807 (San Gregorio 2 Se). Public domain.