Davison Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Burton 4N. 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 8 and the first fall freeze around October 5, a growing season of about 148 days.
- Median at 36°F
- last May 20, first September 25
- Median at 32°F
- last May 8, first October 5
- Median at 28°F
- last April 29, first October 19
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 3 | May 30 | May 26 | May 23 | May 20 | May 17 | May 14 | May 10 | May 6 |
| 32°F | May 22 | May 18 | May 14 | May 11 | May 8 | May 5 | May 3 | Apr 30 | Apr 28 |
| 28°F | May 13 | May 7 | May 3 | May 1 | Apr 29 | Apr 27 | Apr 24 | Apr 21 | Apr 18 |
| 24°F | May 1 | Apr 28 | Apr 24 | Apr 22 | Apr 20 | Apr 18 | Apr 15 | Apr 12 | Apr 8 |
| 20°F | Apr 21 | Apr 18 | Apr 15 | Apr 12 | Apr 9 | Apr 6 | Apr 4 | Apr 1 | Mar 28 |
| 16°F | Apr 11 | Apr 6 | Apr 4 | Apr 1 | Mar 31 | Mar 27 | Mar 22 | Mar 18 | Mar 13 |
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 12 | Sep 17 | Sep 20 | Sep 23 | Sep 25 | Sep 27 | Sep 30 | Oct 3 | Oct 7 |
| 32°F | Sep 22 | Sep 27 | Sep 30 | Oct 3 | Oct 5 | Oct 8 | Oct 11 | Oct 14 | Oct 19 |
| 28°F | Oct 4 | Oct 9 | Oct 14 | Oct 17 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 1 |
| 24°F | Oct 19 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 6 | Nov 10 | Nov 15 |
| 20°F | Nov 1 | Nov 3 | Nov 7 | Nov 10 | Nov 13 | Nov 16 | Nov 20 | Nov 24 | Dec 1 |
| 16°F | Nov 9 | Nov 14 | Nov 17 | Nov 21 | Nov 25 | Nov 29 | Dec 2 | Dec 6 | Dec 14 |
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 | 144 | 138 | 134 | 130 | 126 | 123 | 118 | 113 | 108 |
| 32°F | 166 | 160 | 156 | 151 | 148 | 145 | 141 | 136 | 130 |
| 28°F | 189 | 183 | 178 | 174 | 170 | 167 | 163 | 157 | 151 |
| 24°F | 212 | 206 | 202 | 198 | 194 | 191 | 188 | 184 | 177 |
| 20°F | 240 | 232 | 226 | 221 | 216 | 213 | 209 | 204 | 199 |
| 16°F | 265 | 256 | 250 | 246 | 241 | 237 | 231 | 226 | 219 |
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
- 6,983
- Cooling degree days, base 65°F
- 521
- Growing degree days, base 40°F
- 4,471
- Growing degree days, base 45°F
- 3,406
- Growing degree days, base 50°F
- 2,488
- Growing degree days, base 55°F
- 1,698
- Growing degree days, base 60°F
- 1,029
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,299 | 0 | 0 |
| February | 1,145 | 0 | 0 |
| March | 978 | 1 | 15 |
| April | 616 | 1 | 48 |
| May | 285 | 26 | 245 |
| June | 62 | 101 | 490 |
| July | 18 | 193 | 640 |
| August | 27 | 143 | 581 |
| September | 159 | 51 | 349 |
| October | 471 | 5 | 105 |
| November | 794 | 0 | 15 |
| December | 1,130 | 0 | 1 |
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 7 km from Davison. 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 USC00201150 (Burton 4N). Public domain.