Orem climate

Orem Frost Dates and Growing Season

NOAA 1991-2020 normals for Provo Byu, 6.8 km from Orem, elevation 4570 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Provo Byu. 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 April 18 and the first fall freeze around October 21, a growing season of about 185 days.

Median at 36°F
last May 3, first October 10
Median at 32°F
last April 18, first October 21
Median at 28°F
last March 31, first November 1

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 21May 14May 10May 6May 3Apr 30Apr 28Apr 23Apr 19
32°FMay 5Apr 30Apr 25Apr 21Apr 18Apr 15Apr 10Apr 6Mar 31
28°FApr 17Apr 13Apr 7Apr 3Mar 31Mar 25Mar 19Mar 14Mar 8
24°FMar 31Mar 23Mar 16Mar 11Mar 8Mar 4Mar 1Feb 25Feb 19
20°FMar 9Mar 4Feb 28Feb 26Feb 22Feb 19Feb 15Feb 11Feb 3
16°FFeb 27Feb 22Feb 18Feb 14Feb 9Feb 5Feb 1Jan 25Jan 15

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 28Oct 1Oct 4Oct 7Oct 10Oct 13Oct 15Oct 19Oct 22
32°FOct 7Oct 13Oct 16Oct 18Oct 21Oct 24Oct 27Oct 31Nov 4
28°FOct 19Oct 24Oct 28Oct 30Nov 1Nov 4Nov 7Nov 11Nov 15
24°FOct 30Nov 3Nov 7Nov 11Nov 14Nov 17Nov 20Nov 24Nov 29
20°FNov 9Nov 13Nov 18Nov 22Nov 26Nov 28Dec 1Dec 5Dec 11
16°FNov 18Nov 25Nov 29Dec 2Dec 6Dec 10Dec 15Dec 20Dec 27

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°F178172167163159155151145137
32°F208201194190185180175170163
28°F240232226221216211206201194
24°F271264258253248243238232223
20°F299290284278274270265260254
16°F329318311304298294287281273

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
99% 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
4,968
Cooling degree days, base 65°F
1,205
Growing degree days, base 40°F
6,090
Growing degree days, base 45°F
4,792
Growing degree days, base 50°F
3,665
Growing degree days, base 55°F
2,696
Growing degree days, base 60°F
1,881

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,00701
February76904
March574047
April3744140
May15851367
June30213633
July1427891
August2372835
September54130528
October3278192
November678026
December99501

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 6.8 km from Orem. 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 USC00427064 (Provo Byu). Public domain.