Clive climate

Clive Frost Dates and Growing Season

NOAA 1991-2020 normals for Des Moines Intl AP, 9.7 km from Clive, elevation 957 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Des Moines Intl AP. 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 20, a growing season of about 184 days.

Median at 36°F
last April 29, first October 9
Median at 32°F
last April 18, first October 20
Median at 28°F
last April 8, first October 30

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

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 25Sep 29Oct 3Oct 6Oct 9Oct 12Oct 15Oct 18Oct 22
32°FOct 4Oct 10Oct 14Oct 17Oct 20Oct 23Oct 25Oct 28Nov 1
28°FOct 16Oct 21Oct 25Oct 27Oct 30Nov 1Nov 2Nov 6Nov 11
24°FOct 25Oct 30Nov 1Nov 3Nov 6Nov 9Nov 12Nov 16Nov 21
20°FNov 1Nov 4Nov 8Nov 11Nov 14Nov 17Nov 21Nov 26Dec 2
16°FNov 7Nov 13Nov 16Nov 20Nov 24Nov 27Dec 1Dec 4Dec 10

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°F182176172168163160155151146
32°F203196191187184180175171165
28°F223215211206203199195191185
24°F243235229225220216212207200
20°F263255249244240236231225218
16°F278272266262256252248243234

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
6,178
Cooling degree days, base 65°F
1,070
Growing degree days, base 40°F
5,686
Growing degree days, base 45°F
4,521
Growing degree days, base 50°F
3,476
Growing degree days, base 55°F
2,552
Growing degree days, base 60°F
1,748

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,32200
February1,06803
March796238
April42110139
May15371390
June15230664
July1342806
August4280741
September86120487
October38316180
November773027
December1,15601

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 9.7 km from Clive. 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 USW00014933 (Des Moines Intl AP). Public domain.