Webster climate

Webster Frost Dates and Growing Season

NOAA 1991-2020 normals for Webster, 0.3 km from Webster, elevation 1861 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Webster. 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 May 4 and the first fall freeze around October 6, a growing season of about 156 days.

Median at 36°F
last May 13, first September 28
Median at 32°F
last May 4, first October 6
Median at 28°F
last April 25, first October 16

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 25May 20May 17May 15May 13May 10May 7May 5Apr 30
32°FMay 16May 12May 9May 6May 4May 1Apr 29Apr 26Apr 20
28°FMay 7May 3Apr 30Apr 28Apr 25Apr 22Apr 19Apr 15Apr 10
24°FApr 30Apr 25Apr 21Apr 18Apr 15Apr 12Apr 9Apr 6Apr 2
20°FApr 20Apr 16Apr 12Apr 9Apr 6Apr 4Apr 2Mar 31Mar 24
16°FApr 13Apr 8Apr 5Apr 2Mar 31Mar 29Mar 25Mar 20Mar 15

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 17Sep 20Sep 23Sep 26Sep 28Oct 1Oct 2Oct 6Oct 10
32°FSep 25Sep 29Oct 1Oct 4Oct 6Oct 9Oct 12Oct 15Oct 20
28°FOct 2Oct 6Oct 10Oct 13Oct 16Oct 18Oct 22Oct 24Oct 29
24°FOct 9Oct 15Oct 19Oct 22Oct 24Oct 27Oct 30Nov 2Nov 7
20°FOct 19Oct 24Oct 27Oct 31Nov 1Nov 4Nov 7Nov 11Nov 16
16°FOct 27Nov 1Nov 3Nov 6Nov 9Nov 11Nov 14Nov 18Nov 24

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°F156150146143139136132128123
32°F172166162159156152148143137
28°F191185181176173169165159152
24°F211205200196192188184177171
20°F229222217212208205200195189
16°F245239232228223220216211205

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
8,598
Cooling degree days, base 65°F
529
Growing degree days, base 40°F
4,217
Growing degree days, base 45°F
3,250
Growing degree days, base 50°F
2,392
Growing degree days, base 55°F
1,644
Growing degree days, base 60°F
1,020

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,66100
February1,37800
March1,13304
April679142
May30822228
June70101482
July17203651
August30154589
September19145320
October606372
November1,04905
December1,47900

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 0.3 km from Webster. 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 USC00399004 (Webster). Public domain.