Patterson climate

Patterson Frost Dates and Growing Season

NOAA 1991-2020 normals for Newman, 23.4 km from Patterson, elevation 90 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Newman. 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 26 and the first fall freeze around November 29, a growing season of about 273 days.

Median at 36°F
last April 7, first November 14
Median at 32°F
last February 26, first November 29
Median at 28°F
last January 20, 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°FMay 6Apr 28Apr 21Apr 14Apr 7Mar 31Mar 24Mar 14Mar 3
32°FApr 21Apr 9Mar 26Mar 7Feb 26Feb 16Feb 7Jan 31Jan 18
28°FMar 31Feb 18Feb 1Jan 27Jan 20Jan 12Jan 5Dec 30Dec 21
24°FMar 2Jan 20Jan 13Jan 7Jan 4Dec 31Dec 28Dec 24Dec 16
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 26Nov 1Nov 6Nov 10Nov 14Nov 17Nov 20Nov 24Dec 1
32°FNov 12Nov 17Nov 21Nov 25Nov 29Dec 2Dec 5Dec 10Dec 21
28°FNov 24Dec 1Dec 4Dec 8Dec 12Dec 18Dec 26Jan 2Jan 16
24°FDec 7Dec 12Dec 18Dec 22Dec 27Dec 31Jan 3Jan 8Jan 19
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°F260247236226218212205197184
32°F318305294284273264251235220
28°F365354346339334325316304271
24°F365365365365365364356350338
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
87% of years
24°F or colder
42% of years
20°F or colder
10% of years
16°F or colder
1% 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
1,960
Cooling degree days, base 65°F
1,988
Growing degree days, base 40°F
9,156
Growing degree days, base 45°F
7,363
Growing degree days, base 50°F
5,688
Growing degree days, base 55°F
4,224
Growing degree days, base 60°F
2,996

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January491049
February3170121
March2168261
April11252391
May28184622
June3351798
July0490955
August0443908
September1334783
October42121544
November2596207
December493049

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 23.4 km from Patterson. 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 USC00046168 (Newman). Public domain.