Tanque Verde climate

Tanque Verde Frost Dates and Growing Season

NOAA 1991-2020 normals for Tucson Camp Ave Exp, 19.8 km from Tanque Verde, elevation 2330 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Tucson Camp Ave Exp. 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 20 and the first fall freeze around November 27, a growing season of about 280 days.

Median at 36°F
last March 12, first November 16
Median at 32°F
last February 20, first November 27
Median at 28°F
last January 30, first December 10

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°FApr 5Mar 28Mar 21Mar 16Mar 12Mar 8Mar 4Feb 28Feb 19
32°FMar 11Mar 5Mar 1Feb 25Feb 20Feb 16Feb 11Feb 6Jan 30
28°FFeb 24Feb 15Feb 9Feb 4Jan 30Jan 23Jan 15Jan 7Dec 29
24°FFeb 6Jan 31Jan 22Jan 15Jan 8Dec 31Dec 26Dec 19Dec 9
20°FFeb 1Jan 19Jan 12Jan 9Jan 4Jan 2Dec 31Dec 21Dec 12
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°FNov 1Nov 6Nov 9Nov 13Nov 16Nov 19Nov 22Nov 25Dec 1
32°FNov 10Nov 16Nov 20Nov 24Nov 27Nov 30Dec 3Dec 7Dec 12
28°FNov 23Nov 28Dec 2Dec 6Dec 10Dec 14Dec 20Dec 25Jan 2
24°FDec 1Dec 9Dec 15Dec 20Dec 25Dec 30Jan 3Jan 12Jan 26
20°FDec 12Dec 20Dec 29Jan 1Jan 2Jan 4Jan 7Jan 12Jan 24
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°F274265258252247242236228218
32°F308299292285280275269262253
28°F347338330323316308302294282
24°F365365365365359351343334326
20°F365365365365365365365365363
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
98% of years
24°F or colder
63% of years
20°F or colder
11% of years
16°F or colder
0% 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
1,463
Cooling degree days, base 65°F
3,191
Growing degree days, base 40°F
10,855
Growing degree days, base 45°F
9,048
Growing degree days, base 50°F
7,312
Growing degree days, base 55°F
5,730
Growing degree days, base 60°F
4,356

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January3860115
February2692166
March15029347
April47113516
May4319780
June05891,039
July07081,173
August06711,136
September0513963
October18215662
November17831311
December4110104

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 19.8 km from Tanque Verde. 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 USC00028796 (Tucson Camp Ave Exp). Public domain.