Yuma climate

Yuma Frost Dates and Growing Season

NOAA 1991-2020 normals for Yuma, 0.3 km from Yuma, elevation 4134 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Yuma. 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 1 and the first fall freeze around October 12, a growing season of about 164 days.

Median at 36°F
last May 10, first October 4
Median at 32°F
last May 1, first October 12
Median at 28°F
last April 19, first October 20

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 22May 18May 15May 12May 10May 8May 5May 2Apr 30
32°FMay 13May 9May 6May 3May 1Apr 29Apr 26Apr 22Apr 16
28°FMay 3Apr 30Apr 27Apr 23Apr 19Apr 17Apr 14Apr 9Apr 4
24°FApr 25Apr 19Apr 16Apr 13Apr 10Apr 5Apr 2Mar 28Mar 20
20°FApr 16Apr 11Apr 6Apr 2Mar 30Mar 25Mar 19Mar 13Mar 6
16°FApr 9Apr 2Mar 28Mar 22Mar 15Mar 11Mar 6Mar 2Feb 25

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 26Sep 29Oct 1Oct 4Oct 6Oct 9Oct 11Oct 14
32°FSep 30Oct 3Oct 6Oct 9Oct 12Oct 14Oct 17Oct 20Oct 23
28°FOct 6Oct 12Oct 15Oct 18Oct 20Oct 22Oct 24Oct 27Oct 30
24°FOct 15Oct 19Oct 23Oct 26Oct 29Nov 1Nov 4Nov 8Nov 13
20°FOct 21Oct 26Oct 31Nov 2Nov 6Nov 10Nov 13Nov 17Nov 23
16°FOct 26Nov 1Nov 7Nov 11Nov 14Nov 19Nov 23Nov 26Nov 30

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°F162158153150146143138134128
32°F181175170167164160157153146
28°F200195190185181178175170164
24°F226217211207203198194188181
20°F247239232226220215211205197
16°F268258252245240235228221212

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
5,842
Cooling degree days, base 65°F
1,052
Growing degree days, base 40°F
5,577
Growing degree days, base 45°F
4,379
Growing degree days, base 50°F
3,338
Growing degree days, base 55°F
2,443
Growing degree days, base 60°F
1,683

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,08801
February92403
March724037
April4863104
May22150323
June30212634
July3373835
August8296753
September99111470
October4226152
November762026
December1,07701

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 0.3 km from Yuma. 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 USC00059295 (Yuma). Public domain.