Leupp climate

Leupp Frost Dates and Growing Season

NOAA 1991-2020 normals for Meteor Crater, 29.1 km from Leupp, elevation 5535 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Meteor Crater. 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 30 and the first fall freeze around October 23, a growing season of about 174 days.

Median at 36°F
last May 13, first October 13
Median at 32°F
last April 30, first October 23
Median at 28°F
last April 16, first November 3

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 5May 28May 22May 16May 13May 8May 3Apr 30Apr 24
32°FMay 26May 16May 10May 4Apr 30Apr 27Apr 22Apr 17Apr 8
28°FMay 15May 3Apr 28Apr 22Apr 16Apr 11Apr 6Mar 31Mar 21
24°FApr 30Apr 21Apr 12Apr 4Mar 28Mar 21Mar 14Mar 8Mar 2
20°FApr 11Mar 26Mar 14Mar 9Mar 5Mar 1Feb 25Feb 18Feb 10
16°FMar 9Mar 2Feb 25Feb 19Feb 14Feb 9Feb 4Jan 28Jan 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 25Oct 1Oct 5Oct 9Oct 13Oct 16Oct 19Oct 23Oct 29
32°FOct 1Oct 10Oct 15Oct 19Oct 23Oct 27Oct 31Nov 3Nov 7
28°FOct 14Oct 22Oct 27Oct 31Nov 3Nov 6Nov 10Nov 13Nov 17
24°FOct 25Nov 1Nov 5Nov 9Nov 13Nov 16Nov 19Nov 23Nov 27
20°FNov 7Nov 13Nov 17Nov 21Nov 24Nov 27Dec 1Dec 4Dec 10
16°FNov 18Nov 24Nov 30Dec 3Dec 6Dec 10Dec 14Dec 18Dec 23

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°F176168162156152146140133122
32°F199191186180174169162154143
28°F228217210205199192186177166
24°F258248241233226219211203191
20°F292281274266260254246237221
16°F322313305299293286280271257

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
4,492
Cooling degree days, base 65°F
1,074
Growing degree days, base 40°F
6,195
Growing degree days, base 45°F
4,830
Growing degree days, base 50°F
3,636
Growing degree days, base 55°F
2,619
Growing degree days, base 60°F
1,771

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January89401
February683013
March536052
April3335160
May16449359
June15232667
July1341806
August3293755
September41141551
October27213236
November624034
December92602

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 29.1 km from Leupp. 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 USC00025494 (Meteor Crater). Public domain.