Cedar City climate

Cedar City Frost Dates and Growing Season

NOAA 1991-2020 normals for Cedar City, 2.3 km from Cedar City, elevation 6090 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cedar City. 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 4 and the first fall freeze around October 13, a growing season of about 159 days.

Median at 36°F
last May 20, first October 4
Median at 32°F
last May 4, first October 13
Median at 28°F
last April 22, first October 23

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 8Jun 2May 30May 25May 20May 16May 11May 5Apr 30
32°FMay 28May 19May 14May 9May 4Apr 30Apr 28Apr 24Apr 19
28°FMay 13May 5Apr 30Apr 25Apr 22Apr 18Apr 14Apr 9Apr 3
24°FMay 1Apr 20Apr 14Apr 9Apr 4Apr 1Mar 27Mar 19Mar 12
20°FApr 8Apr 1Mar 25Mar 18Mar 13Mar 8Mar 4Feb 28Feb 21
16°FMar 16Mar 9Mar 5Mar 1Feb 26Feb 22Feb 18Feb 13Feb 2

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 23Sep 27Sep 30Oct 2Oct 4Oct 7Oct 10Oct 14Oct 19
32°FSep 30Oct 3Oct 7Oct 10Oct 13Oct 16Oct 19Oct 22Oct 28
28°FOct 6Oct 12Oct 15Oct 20Oct 23Oct 26Oct 30Nov 3Nov 10
24°FOct 16Oct 22Oct 26Oct 30Nov 2Nov 5Nov 10Nov 14Nov 20
20°FOct 26Nov 2Nov 6Nov 11Nov 15Nov 18Nov 22Nov 26Dec 1
16°FNov 6Nov 13Nov 17Nov 21Nov 25Nov 29Dec 2Dec 7Dec 13

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°F163155148143138134128122115
32°F181174169163159154148142133
28°F206197191187181175170163154
24°F239229222216209203197191181
20°F271262255249242236230221210
16°F301290283278273267262254245

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
5,742
Cooling degree days, base 65°F
804
Growing degree days, base 40°F
5,173
Growing degree days, base 45°F
3,982
Growing degree days, base 50°F
2,965
Growing degree days, base 55°F
2,110
Growing degree days, base 60°F
1,391

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,02200
February85502
March723022
April521167
May27427256
June59140533
July1297761
August4252713
September9683445
October4014144
November740021
December1,04901

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 2.3 km from Cedar City. 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 USC00421259 (Cedar City). Public domain.