Philip climate

Philip Frost Dates and Growing Season

NOAA 1991-2020 normals for Philip AP, 5.3 km from Philip, elevation 2206 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Philip 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 May 11 and the first fall freeze around September 30, a growing season of about 141 days.

Median at 36°F
last May 21, first September 22
Median at 32°F
last May 11, first September 30
Median at 28°F
last May 2, first October 8

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 2May 29May 26May 23May 21May 18May 16May 13May 9
32°FMay 24May 19May 16May 13May 11May 8May 6May 2Apr 29
28°FMay 13May 9May 6May 4May 2Apr 29Apr 26Apr 23Apr 17
24°FMay 5May 1Apr 27Apr 24Apr 21Apr 17Apr 14Apr 10Apr 4
20°FApr 27Apr 21Apr 17Apr 14Apr 10Apr 6Apr 3Mar 31Mar 25
16°FApr 17Apr 11Apr 7Apr 4Apr 1Mar 29Mar 25Mar 19Mar 12

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 9Sep 14Sep 17Sep 20Sep 22Sep 24Sep 27Sep 29Oct 3
32°FSep 17Sep 22Sep 25Sep 28Sep 30Oct 2Oct 5Oct 8Oct 13
28°FSep 26Sep 30Oct 2Oct 5Oct 8Oct 11Oct 14Oct 18Oct 22
24°FOct 2Oct 7Oct 10Oct 14Oct 17Oct 20Oct 22Oct 26Oct 30
20°FOct 10Oct 16Oct 19Oct 23Oct 26Oct 29Nov 1Nov 4Nov 9
16°FOct 19Oct 24Oct 27Oct 31Nov 2Nov 6Nov 9Nov 13Nov 18

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°F141136131127124120116112105
32°F158153149145141137133129123
28°F177172167163160156152147140
24°F198191186183178175170165158
20°F218209205200196192188183175
16°F239231224219214209204198192

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
7,131
Cooling degree days, base 65°F
833
Growing degree days, base 40°F
4,870
Growing degree days, base 45°F
3,797
Growing degree days, base 50°F
2,861
Growing degree days, base 55°F
2,059
Growing degree days, base 60°F
1,380

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,32800
February1,11402
March915015
April583161
May28425243
June58129521
July6315773
August15271721
September13887409
October5226105
November905010
December1,26300

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 5.3 km from Philip. 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 USW00024024 (Philip AP). Public domain.