Willow Park climate

Willow Park Frost Dates and Growing Season

NOAA 1991-2020 normals for Weatherford, 11.2 km from Willow Park, elevation 955 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Weatherford. 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 March 25 and the first fall freeze around November 8, a growing season of about 230 days.

Median at 36°F
last April 7, first October 31
Median at 32°F
last March 25, first November 8
Median at 28°F
last March 10, first November 19

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 25Apr 20Apr 16Apr 12Apr 7Apr 4Mar 31Mar 26Mar 18
32°FApr 15Apr 6Apr 2Mar 30Mar 25Mar 20Mar 15Mar 10Mar 4
28°FMar 31Mar 23Mar 18Mar 13Mar 10Mar 7Mar 3Feb 27Feb 19
24°FMar 16Mar 9Mar 5Mar 1Feb 26Feb 22Feb 16Feb 10Feb 1
20°FMar 5Feb 27Feb 21Feb 14Feb 8Feb 1Jan 28Jan 20Jan 2
16°FFeb 22Feb 12Feb 3Jan 29Jan 24Jan 18Jan 10Dec 31Dec 20

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°FOct 17Oct 21Oct 24Oct 28Oct 31Nov 1Nov 5Nov 8Nov 14
32°FOct 23Oct 29Nov 1Nov 4Nov 8Nov 12Nov 15Nov 19Nov 29
28°FNov 1Nov 7Nov 12Nov 15Nov 19Nov 24Nov 29Dec 3Dec 7
24°FNov 11Nov 18Nov 23Nov 28Dec 2Dec 5Dec 9Dec 16Dec 25
20°FNov 24Dec 1Dec 6Dec 12Dec 18Dec 23Dec 29Jan 6Jan 20
16°FDec 6Dec 13Dec 20Dec 27Jan 2Jan 10Jan 17Jan 26Feb 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°F231222215211206201196190183
32°F255247240234230225219212203
28°F280271265259254248241235226
24°F314301293287280273267260251
20°F350338328320313306299290277
16°F365365365357349340333324313

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
96% of years
16°F or colder
69% 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
2,637
Cooling degree days, base 65°F
2,388
Growing degree days, base 40°F
9,050
Growing degree days, base 45°F
7,426
Growing degree days, base 50°F
5,939
Growing degree days, base 55°F
4,601
Growing degree days, base 60°F
3,413

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January652148
February487485
March31021230
April11977416
May23233676
June0441891
July05811,046
August05691,034
September9334776
October104109477
November33716196
December597265

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 11.2 km from Willow Park. 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 USC00419532 (Weatherford). Public domain.