Mount Ida climate

Mount Ida Frost Dates and Growing Season

NOAA 1991-2020 normals for Mt Ida 3 Se, 4.6 km from Mount Ida, elevation 697 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mt Ida 3 Se. 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 8 and the first fall freeze around October 26, a growing season of about 201 days.

Median at 36°F
last April 19, first October 17
Median at 32°F
last April 8, first October 26
Median at 28°F
last March 26, first November 5

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 5Apr 30Apr 26Apr 23Apr 19Apr 16Apr 12Apr 8Mar 31
32°FApr 26Apr 21Apr 16Apr 12Apr 8Apr 4Mar 31Mar 26Mar 18
28°FApr 14Apr 8Apr 3Mar 31Mar 26Mar 21Mar 16Mar 10Mar 3
24°FApr 4Mar 26Mar 20Mar 14Mar 9Mar 6Mar 1Feb 26Feb 19
20°FMar 18Mar 10Mar 4Feb 28Feb 25Feb 20Feb 15Feb 9Jan 31
16°FMar 5Feb 27Feb 19Feb 12Feb 7Feb 2Jan 28Jan 20Jan 7

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 3Oct 7Oct 10Oct 14Oct 17Oct 20Oct 23Oct 27Nov 1
32°FOct 12Oct 17Oct 21Oct 24Oct 26Oct 29Nov 1Nov 4Nov 12
28°FOct 20Oct 24Oct 30Nov 2Nov 5Nov 8Nov 13Nov 18Nov 25
24°FNov 1Nov 5Nov 10Nov 14Nov 19Nov 23Nov 29Dec 3Dec 9
20°FNov 9Nov 16Nov 22Nov 27Dec 1Dec 5Dec 11Dec 19Dec 26
16°FNov 19Nov 29Dec 5Dec 11Dec 19Dec 24Dec 30Jan 5Jan 17

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°F203195190184180175171166159
32°F227218211206201197192185179
28°F253243237231225219214208198
24°F281271265258251245239232222
20°F314302292286279273267259249
16°F350334327320313306298289278

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
96% 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
3,631
Cooling degree days, base 65°F
1,547
Growing degree days, base 40°F
7,392
Growing degree days, base 45°F
5,910
Growing degree days, base 50°F
4,580
Growing degree days, base 55°F
3,411
Growing degree days, base 60°F
2,399

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January799024
February628133
March4615123
April22531280
May62118521
June4298744
July0437902
August1407871
September29205626
October21039315
November4725109
December742132

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 4.6 km from Mount Ida. 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 USC00034988 (Mt Ida 3 Se). Public domain.