Pablo climate

Pablo Frost Dates and Growing Season

NOAA 1991-2020 normals for Skq Dam, 12.6 km from Pablo, elevation 2730 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Skq Dam. 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 May 15 and the first fall freeze around September 28, a growing season of about 134 days.

Median at 36°F
last June 2, first September 15
Median at 32°F
last May 15, first September 28
Median at 28°F
last May 2, first October 8

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 21Jun 15Jun 10Jun 5Jun 2May 30May 26May 21May 17
32°FJun 1May 27May 21May 18May 15May 12May 9May 6May 3
28°FMay 17May 11May 7May 4May 2Apr 30Apr 26Apr 22Apr 17
24°FMay 2Apr 26Apr 21Apr 18Apr 14Apr 10Apr 6Apr 2Mar 27
20°FApr 11Apr 4Mar 31Mar 29Mar 24Mar 19Mar 15Mar 9Mar 4
16°FMar 29Mar 20Mar 16Mar 12Mar 8Mar 5Mar 2Feb 26Feb 18

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 1Sep 5Sep 10Sep 13Sep 15Sep 19Sep 21Sep 24Sep 29
32°FSep 13Sep 19Sep 23Sep 26Sep 28Oct 1Oct 3Oct 6Oct 11
28°FSep 24Sep 30Oct 3Oct 5Oct 8Oct 12Oct 15Oct 18Oct 24
24°FOct 4Oct 9Oct 13Oct 18Oct 22Oct 25Oct 29Nov 1Nov 6
20°FOct 13Oct 21Oct 26Oct 30Nov 2Nov 6Nov 10Nov 16Nov 21
16°FOct 24Oct 31Nov 4Nov 8Nov 13Nov 17Nov 22Nov 26Dec 2

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°F12611911310810399959080
32°F152146142137134130126120112
28°F178171166162158154149144137
24°F214206199193189184179173165
20°F250240233228223216211205196
16°F278267261253247242237232222

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
100% of years
16°F or colder
100% 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
7,453
Cooling degree days, base 65°F
263
Growing degree days, base 40°F
3,556
Growing degree days, base 45°F
2,570
Growing degree days, base 50°F
1,751
Growing degree days, base 55°F
1,085
Growing degree days, base 60°F
593

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,20000
February1,01100
March88402
April626019
May3892125
June20218270
July46121539
August51111526
September24411234
October642035
November96501
December1,19500

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 12.6 km from Pablo. 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 USC00246640 (Skq Dam). Public domain.