Bloomer climate

Bloomer Frost Dates and Growing Season

NOAA 1991-2020 normals for Bloomer, 1 km from Bloomer, elevation 990 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bloomer. 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 5 and the first fall freeze around October 3, a growing season of about 151 days.

Median at 36°F
last May 16, first September 25
Median at 32°F
last May 5, first October 3
Median at 28°F
last April 26, first October 15

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 31May 26May 22May 19May 16May 14May 10May 7May 3
32°FMay 19May 14May 11May 8May 5May 3May 1Apr 28Apr 23
28°FMay 8May 4May 1Apr 29Apr 26Apr 23Apr 19Apr 16Apr 10
24°FApr 29Apr 24Apr 21Apr 18Apr 15Apr 12Apr 8Apr 5Apr 2
20°FApr 20Apr 15Apr 11Apr 8Apr 5Apr 3Apr 1Mar 30Mar 23
16°FApr 13Apr 7Apr 4Apr 1Mar 30Mar 27Mar 24Mar 20Mar 14

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 11Sep 15Sep 19Sep 23Sep 25Sep 28Oct 1Oct 3Oct 7
32°FSep 20Sep 26Sep 28Oct 1Oct 3Oct 6Oct 9Oct 12Oct 17
28°FOct 1Oct 5Oct 9Oct 12Oct 15Oct 17Oct 20Oct 24Oct 28
24°FOct 12Oct 17Oct 21Oct 23Oct 26Oct 29Oct 31Nov 3Nov 9
20°FOct 23Oct 28Oct 31Nov 1Nov 4Nov 8Nov 11Nov 15Nov 20
16°FNov 1Nov 4Nov 8Nov 11Nov 15Nov 18Nov 20Nov 24Nov 28

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°F149142138134130127123118112
32°F168162158154151147143137132
28°F191184178174171167162158152
24°F212206201197193189184179172
20°F229224220216212209205200193
16°F248241236232229225220216209

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
8,356
Cooling degree days, base 65°F
497
Growing degree days, base 40°F
4,197
Growing degree days, base 45°F
3,221
Growing degree days, base 50°F
2,357
Growing degree days, base 55°F
1,608
Growing degree days, base 60°F
983

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,63200
February1,35900
March1,10807
April648246
May28725239
June67109493
July17187635
August36130560
September20142308
October591265
November98705
December1,42300

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 1 km from Bloomer. 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 USC00470904 (Bloomer). Public domain.