Cheboygan Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Cheboygan. 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 11 and the first fall freeze around October 11, a growing season of about 152 days.
- Median at 36°F
- last May 24, first October 1
- Median at 32°F
- last May 11, first October 11
- Median at 28°F
- last April 30, first October 22
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.
| Threshold | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 7 | Jun 2 | May 30 | May 27 | May 24 | May 22 | May 19 | May 15 | May 10 |
| 32°F | May 25 | May 21 | May 18 | May 14 | May 11 | May 9 | May 5 | May 2 | Apr 29 |
| 28°F | May 15 | May 9 | May 6 | May 3 | Apr 30 | Apr 28 | Apr 25 | Apr 21 | Apr 15 |
| 24°F | May 3 | Apr 28 | Apr 24 | Apr 21 | Apr 18 | Apr 15 | Apr 12 | Apr 9 | Apr 5 |
| 20°F | Apr 23 | Apr 18 | Apr 14 | Apr 10 | Apr 8 | Apr 5 | Apr 3 | Apr 1 | Mar 27 |
| 16°F | Apr 14 | Apr 9 | Apr 5 | Apr 3 | Apr 2 | Mar 31 | Mar 28 | Mar 24 | Mar 18 |
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.
| Threshold | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 17 | Sep 22 | Sep 25 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 9 | Oct 14 |
| 32°F | Sep 24 | Oct 1 | Oct 4 | Oct 7 | Oct 11 | Oct 13 | Oct 17 | Oct 21 | Oct 27 |
| 28°F | Oct 3 | Oct 10 | Oct 15 | Oct 18 | Oct 22 | Oct 26 | Oct 30 | Nov 2 | Nov 8 |
| 24°F | Oct 15 | Oct 23 | Oct 30 | Nov 2 | Nov 4 | Nov 7 | Nov 11 | Nov 15 | Nov 21 |
| 20°F | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 16 | Nov 20 | Nov 24 | Nov 28 | Dec 3 |
| 16°F | Nov 8 | Nov 14 | Nov 19 | Nov 24 | Nov 27 | Dec 1 | Dec 3 | Dec 8 | Dec 15 |
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.
| Threshold | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | 147 | 140 | 136 | 131 | 128 | 125 | 121 | 116 | 108 |
| 32°F | 173 | 166 | 160 | 156 | 152 | 147 | 143 | 138 | 131 |
| 28°F | 194 | 188 | 184 | 179 | 175 | 170 | 165 | 160 | 152 |
| 24°F | 221 | 214 | 209 | 205 | 200 | 196 | 191 | 184 | 176 |
| 20°F | 244 | 236 | 232 | 226 | 221 | 216 | 213 | 206 | 197 |
| 16°F | 263 | 256 | 250 | 245 | 240 | 236 | 231 | 224 | 215 |
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
- 8,024
- Cooling degree days, base 65°F
- 308
- Growing degree days, base 40°F
- 3,707
- Growing degree days, base 45°F
- 2,753
- Growing degree days, base 50°F
- 1,935
- Growing degree days, base 55°F
- 1,245
- Growing degree days, base 60°F
- 693
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,417 | 0 | 0 |
| February | 1,270 | 0 | 0 |
| March | 1,155 | 0 | 2 |
| April | 764 | 0 | 15 |
| May | 422 | 5 | 120 |
| June | 139 | 45 | 359 |
| July | 41 | 120 | 544 |
| August | 45 | 100 | 521 |
| September | 200 | 35 | 297 |
| October | 542 | 3 | 71 |
| November | 852 | 0 | 7 |
| December | 1,180 | 0 | 0 |
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 0.7 km from Cheboygan. 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 USC00201492 (Cheboygan). Public domain.