Ten Mile Run climate

Ten Mile Run Frost Dates and Growing Season

NOAA 1991-2020 normals for Wertsville 4 Ne, 15.6 km from Ten Mile Run, elevation 283 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Wertsville 4 Ne. 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 16 and the first fall freeze around October 27, a growing season of about 192 days.

Median at 36°F
last April 30, first October 14
Median at 32°F
last April 16, first October 27
Median at 28°F
last April 3, first November 7

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 9May 5May 2Apr 30Apr 26Apr 23Apr 20Apr 15
32°FMay 1Apr 25Apr 21Apr 18Apr 16Apr 12Apr 9Apr 6Apr 3
28°FApr 16Apr 11Apr 7Apr 4Apr 3Apr 1Mar 30Mar 26Mar 20
24°FApr 4Apr 1Mar 30Mar 27Mar 24Mar 20Mar 17Mar 13Mar 8
20°FMar 28Mar 23Mar 19Mar 16Mar 13Mar 9Mar 5Mar 2Feb 24
16°FMar 18Mar 13Mar 9Mar 5Mar 2Feb 28Feb 24Feb 18Feb 10

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 1Oct 5Oct 8Oct 10Oct 14Oct 17Oct 21Oct 25Oct 30
32°FOct 10Oct 16Oct 20Oct 24Oct 27Oct 30Nov 1Nov 4Nov 9
28°FOct 25Oct 31Nov 2Nov 4Nov 7Nov 10Nov 13Nov 17Nov 23
24°FNov 5Nov 10Nov 13Nov 17Nov 20Nov 24Nov 28Dec 1Dec 7
20°FNov 14Nov 20Nov 25Nov 30Dec 2Dec 6Dec 12Dec 18Dec 26
16°FNov 29Dec 2Dec 8Dec 15Dec 20Dec 24Dec 29Jan 3Jan 11

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°F187181175171167164159155148
32°F213206201196192188184178171
28°F239231225221217214210206199
24°F268258253248243240235230223
20°F292283276271266260255249242
16°F315307301295290285281275265

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
5,411
Cooling degree days, base 65°F
871
Growing degree days, base 40°F
5,548
Growing degree days, base 45°F
4,313
Growing degree days, base 50°F
3,232
Growing degree days, base 55°F
2,295
Growing degree days, base 60°F
1,509

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,08602
February92703
March785023
April4298118
May17944336
June31169588
July1302766
August5240701
September7598474
October34710177
November629038
December91808

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 15.6 km from Ten Mile Run. 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 USC00289363 (Wertsville 4 Ne). Public domain.