Westpoint climate

Westpoint Frost Dates and Growing Season

NOAA 1991-2020 normals for Lafayette 8 S, 13.1 km from Westpoint, elevation 732 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lafayette 8 S. 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 20 and the first fall freeze around October 20, a growing season of about 182 days.

Median at 36°F
last May 1, first October 9
Median at 32°F
last April 20, first October 20
Median at 28°F
last April 7, first October 31

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 17May 11May 6May 3May 1Apr 29Apr 26Apr 22Apr 17
32°FMay 6May 1Apr 27Apr 23Apr 20Apr 17Apr 14Apr 11Apr 6
28°FApr 24Apr 19Apr 15Apr 11Apr 7Apr 5Apr 2Mar 30Mar 24
24°FApr 14Apr 7Apr 3Mar 31Mar 29Mar 26Mar 22Mar 18Mar 12
20°FApr 2Mar 30Mar 26Mar 21Mar 19Mar 15Mar 12Mar 7Mar 2
16°FMar 28Mar 20Mar 16Mar 13Mar 10Mar 6Mar 3Feb 27Feb 19

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 25Oct 1Oct 4Oct 6Oct 9Oct 12Oct 14Oct 17Oct 21
32°FOct 4Oct 10Oct 14Oct 17Oct 20Oct 22Oct 25Oct 28Nov 2
28°FOct 17Oct 21Oct 25Oct 29Oct 31Nov 3Nov 5Nov 9Nov 16
24°FOct 30Nov 2Nov 5Nov 8Nov 11Nov 15Nov 19Nov 23Nov 29
20°FNov 6Nov 11Nov 15Nov 19Nov 22Nov 26Nov 30Dec 3Dec 9
16°FNov 12Nov 19Nov 24Nov 28Dec 1Dec 4Dec 8Dec 13Dec 21

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°F180173168164160156151146139
32°F201195190186182177173166157
28°F226219213208204200194190182
24°F251242236231227223218213205
20°F274266259253248243238233226
16°F293285278273267262256251241

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
5,799
Cooling degree days, base 65°F
961
Growing degree days, base 40°F
5,672
Growing degree days, base 45°F
4,475
Growing degree days, base 50°F
3,408
Growing degree days, base 55°F
2,463
Growing degree days, base 60°F
1,644

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,22602
February1,00204
March787241
April41911145
May15584403
June20217647
July4280741
August7232690
September80115488
October34620203
November698140
December1,05505

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 13.1 km from Westpoint. 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 USC00124715 (Lafayette 8 S). Public domain.