Ottoville climate

Ottoville Frost Dates and Growing Season

NOAA 1991-2020 normals for Van Wert 1 S, 22.3 km from Ottoville, elevation 790 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Van Wert 1 S. 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 21 and the first fall freeze around October 26, a growing season of about 187 days.

Median at 36°F
last April 30, first October 14
Median at 32°F
last April 21, first October 26
Median at 28°F
last April 9, 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 15May 10May 7May 3Apr 30Apr 28Apr 25Apr 22Apr 17
32°FMay 6Apr 30Apr 26Apr 23Apr 21Apr 18Apr 16Apr 12Apr 7
28°FApr 24Apr 19Apr 15Apr 13Apr 9Apr 6Apr 4Apr 1Mar 27
24°FApr 15Apr 8Apr 5Apr 2Mar 31Mar 28Mar 24Mar 20Mar 15
20°FApr 5Mar 31Mar 28Mar 25Mar 21Mar 17Mar 14Mar 10Mar 4
16°FMar 28Mar 22Mar 17Mar 14Mar 11Mar 8Mar 5Mar 1Feb 22

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 1Oct 5Oct 9Oct 12Oct 14Oct 17Oct 20Oct 23Oct 27
32°FOct 13Oct 18Oct 21Oct 23Oct 26Oct 29Nov 1Nov 3Nov 7
28°FOct 23Oct 29Nov 1Nov 2Nov 5Nov 7Nov 11Nov 14Nov 20
24°FNov 3Nov 6Nov 9Nov 13Nov 16Nov 20Nov 23Nov 28Dec 3
20°FNov 8Nov 13Nov 18Nov 22Nov 26Nov 29Dec 2Dec 7Dec 15
16°FNov 16Nov 23Nov 27Dec 1Dec 5Dec 9Dec 15Dec 21Dec 26

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°F184178173169165161157152146
32°F206199194190187183178174167
28°F229222217214209206201196187
24°F253246240235230226222217211
20°F277267261256251247242236228
16°F298290283276271266261255247

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
5,995
Cooling degree days, base 65°F
937
Growing degree days, base 40°F
5,502
Growing degree days, base 45°F
4,332
Growing degree days, base 50°F
3,291
Growing degree days, base 55°F
2,378
Growing degree days, base 60°F
1,593

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,22901
February1,02802
March841127
April4648117
May17569370
June25205630
July2295758
August6237696
September84106475
October36716180
November713032
December1,06204

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 22.3 km from Ottoville. 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 USC00338609 (Van Wert 1 S). Public domain.