Saint Joseph climate

Saint Joseph Frost Dates and Growing Season

NOAA 1991-2020 normals for La Crosse WFO, 12.7 km from Saint Joseph, elevation 1307 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for La Crosse WFO. 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 27 and the first fall freeze around October 13, a growing season of about 167 days.

Median at 36°F
last May 7, first October 1
Median at 32°F
last April 27, first October 13
Median at 28°F
last April 16, first October 25

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 22May 17May 14May 10May 7May 4May 1Apr 29Apr 24
32°FMay 12May 6May 2Apr 30Apr 27Apr 23Apr 21Apr 17Apr 12
28°FMay 1Apr 26Apr 22Apr 19Apr 16Apr 13Apr 9Apr 6Apr 3
24°FApr 20Apr 14Apr 10Apr 8Apr 6Apr 3Apr 1Mar 30Mar 23
20°FApr 10Apr 5Apr 3Apr 1Mar 30Mar 27Mar 23Mar 18Mar 13
16°FApr 3Mar 31Mar 28Mar 24Mar 21Mar 17Mar 14Mar 11Mar 6

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 20Sep 25Sep 27Sep 30Oct 1Oct 5Oct 7Oct 11Oct 16
32°FSep 28Oct 2Oct 6Oct 10Oct 13Oct 16Oct 19Oct 23Oct 29
28°FOct 10Oct 16Oct 19Oct 22Oct 25Oct 29Nov 1Nov 4Nov 9
24°FOct 22Oct 27Oct 31Nov 1Nov 4Nov 7Nov 10Nov 14Nov 19
20°FNov 1Nov 4Nov 7Nov 10Nov 13Nov 16Nov 19Nov 22Nov 27
16°FNov 7Nov 11Nov 15Nov 17Nov 21Nov 23Nov 26Nov 30Dec 4

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°F166160154150147143139134128
32°F187180175171167163159154146
28°F210203198193189184180175168
24°F232224219214210206201196190
20°F250242236232228224219214208
16°F265258252249244240235230223

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
7,593
Cooling degree days, base 65°F
543
Growing degree days, base 40°F
4,525
Growing degree days, base 45°F
3,487
Growing degree days, base 50°F
2,561
Growing degree days, base 55°F
1,755
Growing degree days, base 60°F
1,079

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,52000
February1,23901
March1,001115
April580372
May26029262
June54111507
July13188640
August21152595
September16254353
October5106103
November909012
December1,32400

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 12.7 km from Saint Joseph. 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 USC00474373 (La Crosse WFO). Public domain.