Arlington climate

Arlington Frost Dates and Growing Season

NOAA 1991-2020 normals for Arlington, 0.6 km from Arlington, elevation 277 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Arlington. 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 6 and the first fall freeze around October 21, a growing season of about 196 days.

Median at 36°F
last April 27, first October 11
Median at 32°F
last April 6, first October 21
Median at 28°F
last March 19, first November 3

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 10May 5May 2Apr 29Apr 27Apr 24Apr 20Apr 15Apr 9
32°FApr 28Apr 21Apr 16Apr 11Apr 6Apr 3Mar 31Mar 27Mar 22
28°FApr 8Apr 1Mar 27Mar 23Mar 19Mar 14Mar 10Mar 6Mar 1
24°FMar 20Mar 13Mar 8Mar 4Mar 1Feb 27Feb 23Feb 16Feb 8
20°FMar 4Feb 28Feb 24Feb 19Feb 14Feb 8Jan 31Jan 15Jan 4
16°FFeb 26Feb 18Feb 11Feb 4Jan 26Jan 15Jan 8Dec 31Dec 11

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 29Oct 3Oct 5Oct 8Oct 11Oct 14Oct 16Oct 19Oct 25
32°FOct 6Oct 11Oct 15Oct 18Oct 21Oct 25Oct 28Nov 1Nov 7
28°FOct 18Oct 23Oct 27Oct 30Nov 3Nov 6Nov 10Nov 15Nov 22
24°FOct 26Nov 1Nov 6Nov 12Nov 17Nov 22Nov 26Dec 1Dec 12
20°FNov 4Nov 13Nov 22Nov 28Dec 3Dec 9Dec 18Dec 31Jan 12
16°FNov 13Nov 27Dec 4Dec 9Dec 17Dec 27Jan 3Jan 12Jan 29

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°F190182177172168164160155149
32°F219212205201196191187181174
28°F255245239234230224219212203
24°F296283275268262255248242231
20°F338323314306297289281273260
16°F365354343334326318310301286

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
98% of years
16°F or colder
86% 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
4,820
Cooling degree days, base 65°F
970
Growing degree days, base 40°F
5,795
Growing degree days, base 45°F
4,456
Growing degree days, base 50°F
3,323
Growing degree days, base 55°F
2,381
Growing degree days, base 60°F
1,597

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January92200
February73502
March600019
April3672119
May14945362
June37132545
July3354817
August3327789
September58104497
October3545157
November678015
December91402

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 0.6 km from Arlington. 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 USC00350265 (Arlington). Public domain.