Onalaska climate

Onalaska Frost Dates and Growing Season

NOAA 1991-2020 normals for Livingston 2 Nne, 19.6 km from Onalaska, elevation 178 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Livingston 2 Nne. 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 March 1 and the first fall freeze around November 24, a growing season of about 269 days.

Median at 36°F
last March 17, first November 12
Median at 32°F
last March 1, first November 24
Median at 28°F
last February 14, first December 12

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°FApr 9Apr 3Mar 30Mar 24Mar 17Mar 12Mar 5Feb 28Feb 23
32°FMar 27Mar 19Mar 12Mar 5Mar 1Feb 26Feb 22Feb 15Feb 4
28°FMar 12Mar 4Feb 26Feb 20Feb 14Feb 8Feb 1Jan 27Jan 13
24°FMar 1Feb 17Feb 10Feb 4Jan 31Jan 26Jan 21Jan 8Dec 30
20°FFeb 13Feb 5Jan 31Jan 28Jan 24Jan 14Jan 9Jan 5Dec 31
16°F–––––––––

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 30Nov 1Nov 5Nov 8Nov 12Nov 15Nov 19Nov 25Dec 1
32°FNov 3Nov 9Nov 14Nov 18Nov 24Nov 29Dec 3Dec 10Dec 23
28°FNov 13Nov 21Nov 30Dec 4Dec 12Dec 22Jan 1Jan 6Jan 23
24°FNov 27Dec 7Dec 19Dec 31Jan 2Jan 8Jan 15Jan 27Feb 7
20°FDec 26Jan 1Jan 3Jan 6Jan 9Jan 16Jan 23Feb 1Feb 6
16°F–––––––––

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°F271262254248241235228221210
32°F306291282275269261254246235
28°F344330320310302295286276262
24°F365365365353341334327313299
20°F365365365365365365365352334
16°F365365365365365365365365365

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
98% of years
24°F or colder
71% of years
20°F or colder
31% of years
16°F or colder
5% 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
1,647
Cooling degree days, base 65°F
2,995
Growing degree days, base 40°F
10,506
Growing degree days, base 45°F
8,755
Growing degree days, base 50°F
7,096
Growing degree days, base 55°F
5,574
Growing degree days, base 60°F
4,204

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January44710130
February31219179
March16866376
April57144538
May5336797
June0510960
July06181,083
August06151,080
September2419867
October49190607
November21052317
December39916162

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 19.6 km from Onalaska. 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 USC00415271 (Livingston 2 Nne). Public domain.