Foreston climate

Foreston Frost Dates and Growing Season

NOAA 1991-2020 normals for Milaca, 4.3 km from Foreston, elevation 1064 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Milaca. 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 8 and the first fall freeze around October 1, a growing season of about 143 days.

Median at 36°F
last May 20, first September 22
Median at 32°F
last May 8, first October 1
Median at 28°F
last April 28, first October 11

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°FJun 3May 31May 27May 23May 20May 18May 14May 10May 5
32°FMay 26May 20May 16May 12May 8May 5May 2Apr 30Apr 25
28°FMay 14May 8May 3Apr 30Apr 28Apr 25Apr 22Apr 19Apr 14
24°FMay 1Apr 27Apr 24Apr 21Apr 18Apr 15Apr 11Apr 8Apr 4
20°FApr 22Apr 18Apr 13Apr 10Apr 7Apr 5Apr 3Apr 1Mar 27
16°FApr 14Apr 8Apr 5Apr 3Apr 2Mar 31Mar 28Mar 23Mar 18

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

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°F142135130126122118114109102
32°F162156151147143138134129121
28°F184177172168163159155149143
24°F207199194189185181177172163
20°F225219214210207203198192185
16°F242236231226221218214210203

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
8,808
Cooling degree days, base 65°F
378
Growing degree days, base 40°F
3,899
Growing degree days, base 45°F
2,953
Growing degree days, base 50°F
2,122
Growing degree days, base 55°F
1,408
Growing degree days, base 60°F
823

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,69100
February1,40400
March1,16103
April698131
May33716193
June8576442
July19154600
August42101524
September22729272
October623154
November1,04903
December1,47200

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 4.3 km from Foreston. 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 USC00215392 (Milaca). Public domain.