Bridgetown climate

Bridgetown Frost Dates and Growing Season

NOAA 1991-2020 normals for Cheviot, 1.2 km from Bridgetown, elevation 891 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cheviot. 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 17 and the first fall freeze around October 26, a growing season of about 191 days.

Median at 36°F
last April 29, first October 16
Median at 32°F
last April 17, first October 26
Median at 28°F
last April 4, first November 4

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 13May 8May 5May 1Apr 29Apr 25Apr 21Apr 18Apr 14
32°FMay 5Apr 30Apr 24Apr 20Apr 17Apr 14Apr 11Apr 7Apr 2
28°FApr 21Apr 15Apr 11Apr 7Apr 4Apr 2Mar 31Mar 27Mar 20
24°FApr 8Apr 3Mar 31Mar 28Mar 25Mar 22Mar 18Mar 15Mar 8
20°FMar 30Mar 24Mar 21Mar 17Mar 15Mar 12Mar 8Mar 3Feb 23
16°FMar 21Mar 16Mar 12Mar 7Mar 4Mar 1Feb 25Feb 18Feb 9

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 3Oct 7Oct 10Oct 13Oct 16Oct 18Oct 21Oct 24Oct 29
32°FOct 11Oct 17Oct 21Oct 23Oct 26Oct 28Oct 31Nov 3Nov 7
28°FOct 22Oct 28Oct 31Nov 2Nov 4Nov 7Nov 11Nov 15Nov 22
24°FNov 1Nov 4Nov 8Nov 12Nov 16Nov 20Nov 24Nov 29Dec 4
20°FNov 8Nov 16Nov 20Nov 25Nov 29Dec 2Dec 6Dec 11Dec 20
16°FNov 19Nov 27Dec 1Dec 7Dec 11Dec 17Dec 22Dec 26Dec 31

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°F190183178174170166161157149
32°F211204199195191186182176168
28°F237229223218214210206201193
24°F261252245241236231226220213
20°F287278270265259254248241232
16°F310300294288283277272265255

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
5,143
Cooling degree days, base 65°F
1,099
Growing degree days, base 40°F
6,118
Growing degree days, base 45°F
4,843
Growing degree days, base 50°F
3,702
Growing degree days, base 55°F
2,691
Growing degree days, base 60°F
1,824

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,09106
February886011
March708357
April34815190
May12988429
June15223658
July1324787
August3291753
September60134526
October31020222
November640151
December952011

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 1.2 km from Bridgetown. 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 USC00331515 (Cheviot). Public domain.