Scranton climate

Scranton Frost Dates and Growing Season

NOAA 1991-2020 normals for Lake City 2 Se, 6.1 km from Scranton, elevation 75 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lake City 2 Se. 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 20 and the first fall freeze around November 13, a growing season of about 240 days.

Median at 36°F
last April 2, first November 2
Median at 32°F
last March 20, first November 13
Median at 28°F
last March 4, first November 28

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 18Apr 12Apr 8Apr 5Apr 2Mar 31Mar 26Mar 22Mar 15
32°FApr 5Apr 1Mar 28Mar 24Mar 20Mar 16Mar 11Mar 5Feb 25
28°FMar 26Mar 19Mar 14Mar 9Mar 4Feb 27Feb 23Feb 13Feb 4
24°FMar 12Mar 4Feb 27Feb 19Feb 11Feb 4Jan 31Jan 24Jan 13
20°FFeb 28Feb 16Feb 6Feb 1Jan 28Jan 22Jan 16Jan 8Dec 28
16°FFeb 7Jan 31Jan 29Jan 22Jan 18Jan 13Jan 9Jan 1Dec 25

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 20Oct 25Oct 29Nov 1Nov 2Nov 5Nov 8Nov 12Nov 19
32°FOct 30Nov 2Nov 5Nov 9Nov 13Nov 17Nov 22Nov 29Dec 4
28°FNov 7Nov 13Nov 18Nov 23Nov 28Dec 2Dec 6Dec 13Dec 25
24°FNov 20Nov 28Dec 2Dec 7Dec 13Dec 21Dec 29Jan 4Jan 14
20°FDec 2Dec 10Dec 21Dec 29Jan 2Jan 8Jan 14Jan 20Feb 1
16°FDec 17Dec 27Jan 1Jan 5Jan 10Jan 15Jan 19Jan 27Feb 2

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°F241232226221217212208202194
32°F272261253248240235229224216
28°F304293283276268262255248236
24°F342331320311305298288279268
20°F365365357347338333325315302
16°F365365365365365365355345332

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
99% of years
20°F or colder
81% of years
16°F or colder
42% 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
2,415
Cooling degree days, base 65°F
2,148
Growing degree days, base 40°F
8,952
Growing degree days, base 45°F
7,283
Growing degree days, base 50°F
5,752
Growing degree days, base 55°F
4,381
Growing degree days, base 60°F
3,175

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January593371
February448493
March31817216
April11876412
May20219663
June1401851
July0522987
August0477942
September4312757
October9497471
November31115192
December509697

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 6.1 km from Scranton. 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 USC00384886 (Lake City 2 Se). Public domain.