Phillips County climate

Phillips County Frost Dates and Growing Season

NOAA 1991-2020 normals for Phillipsburg #2, 4.7 km from Phillips County, elevation 1888 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Phillipsburg #2. 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 26 and the first fall freeze around October 16, a growing season of about 172 days.

Median at 36°F
last May 3, first October 7
Median at 32°F
last April 26, first October 16
Median at 28°F
last April 15, first October 23

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

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 26Sep 29Oct 2Oct 5Oct 7Oct 9Oct 12Oct 15Oct 19
32°FOct 1Oct 6Oct 11Oct 13Oct 16Oct 18Oct 20Oct 23Oct 27
28°FOct 11Oct 16Oct 19Oct 21Oct 23Oct 26Oct 29Nov 1Nov 5
24°FOct 19Oct 23Oct 27Oct 30Nov 2Nov 4Nov 7Nov 11Nov 17
20°FOct 26Nov 1Nov 4Nov 7Nov 10Nov 14Nov 18Nov 21Nov 27
16°FNov 2Nov 7Nov 12Nov 16Nov 20Nov 24Nov 27Dec 1Dec 7

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°F173167163160156153149144139
32°F189184179175172168164161154
28°F210204199194190187183178172
24°F231224218214210206202196189
20°F250243238233228224219212205
16°F271265259254248243238230221

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
5,636
Cooling degree days, base 65°F
1,359
Growing degree days, base 40°F
6,084
Growing degree days, base 45°F
4,869
Growing degree days, base 50°F
3,796
Growing degree days, base 55°F
2,856
Growing degree days, base 60°F
2,043

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,14500
February94303
March717140
April4226129
May15972386
June15285720
July1442906
August2377840
September68158542
October35419201
November725029
December1,08501

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 4.7 km from Phillips 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 USC00146378 (Phillipsburg #2). Public domain.