Page County climate

Page County Frost Dates and Growing Season

NOAA 1991-2020 normals for Clarinda, 11.1 km from Page County, elevation 980 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Clarinda. 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 25 and the first fall freeze around October 11, a growing season of about 168 days.

Median at 36°F
last May 4, first October 1
Median at 32°F
last April 25, first October 11
Median at 28°F
last April 14, first October 21

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 18May 12May 8May 6May 4May 1Apr 30Apr 26Apr 22
32°FMay 7May 3Apr 30Apr 27Apr 25Apr 22Apr 18Apr 15Apr 11
28°FApr 29Apr 24Apr 21Apr 17Apr 14Apr 11Apr 9Apr 5Apr 1
24°FApr 20Apr 14Apr 10Apr 6Apr 4Apr 1Mar 29Mar 25Mar 18
20°FApr 9Apr 4Apr 1Mar 29Mar 26Mar 22Mar 18Mar 14Mar 8
16°FMar 31Mar 27Mar 22Mar 18Mar 15Mar 11Mar 8Mar 4Feb 28

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 17Sep 23Sep 27Sep 29Oct 1Oct 4Oct 6Oct 9Oct 15
32°FSep 26Oct 1Oct 4Oct 8Oct 11Oct 14Oct 17Oct 20Oct 24
28°FOct 6Oct 13Oct 16Oct 19Oct 21Oct 24Oct 27Oct 30Nov 2
24°FOct 18Oct 22Oct 25Oct 28Oct 31Nov 1Nov 3Nov 7Nov 13
20°FOct 27Nov 1Nov 3Nov 5Nov 8Nov 11Nov 14Nov 18Nov 24
16°FNov 4Nov 7Nov 11Nov 14Nov 18Nov 21Nov 25Nov 30Dec 5

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°F168161157153150146143137131
32°F189181177172168164160155148
28°F208201197192189185181176168
24°F230222217213208204200195188
20°F250242237232227222217212205
16°F271263257252247242237231223

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
6,292
Cooling degree days, base 65°F
965
Growing degree days, base 40°F
5,485
Growing degree days, base 45°F
4,333
Growing degree days, base 50°F
3,306
Growing degree days, base 55°F
2,399
Growing degree days, base 60°F
1,618

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,32400
February1,06302
March803136
April4448128
May16966372
June18215646
July3311773
August7249707
September105101450
October40014169
November792023
December1,16201

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 11.1 km from Page County. 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 USC00131533 (Clarinda). Public domain.