Eden Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Fond Du Lac Wwtp. 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 1 and the first fall freeze around October 12, a growing season of about 162 days.
- Median at 36°F
- last May 12, first October 2
- Median at 32°F
- last May 1, first October 12
- Median at 28°F
- last April 20, first October 24
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 | May 28 | May 23 | May 19 | May 15 | May 12 | May 8 | May 6 | May 3 | Apr 29 |
| 32°F | May 17 | May 12 | May 8 | May 5 | May 1 | Apr 29 | Apr 26 | Apr 22 | Apr 18 |
| 28°F | May 5 | Apr 30 | Apr 27 | Apr 23 | Apr 20 | Apr 17 | Apr 14 | Apr 11 | Apr 5 |
| 24°F | Apr 21 | Apr 18 | Apr 14 | Apr 11 | Apr 8 | Apr 5 | Apr 3 | Apr 1 | Mar 26 |
| 20°F | Apr 12 | Apr 7 | Apr 4 | Apr 2 | Apr 1 | Mar 29 | Mar 25 | Mar 21 | Mar 17 |
| 16°F | Apr 4 | Mar 31 | Mar 28 | Mar 25 | Mar 22 | Mar 19 | Mar 16 | Mar 13 | Mar 9 |
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 21 | Sep 25 | Sep 28 | Sep 30 | Oct 2 | Oct 4 | Oct 7 | Oct 10 | Oct 15 |
| 32°F | Sep 28 | Oct 2 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 17 | Oct 21 | Oct 25 |
| 28°F | Oct 5 | Oct 12 | Oct 16 | Oct 20 | Oct 24 | Oct 26 | Oct 29 | Oct 31 | Nov 4 |
| 24°F | Oct 18 | Oct 25 | Oct 29 | Nov 1 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 17 |
| 20°F | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 15 | Nov 18 | Nov 21 | Nov 26 |
| 16°F | Nov 7 | Nov 12 | Nov 16 | Nov 19 | Nov 21 | Nov 24 | Nov 26 | Nov 30 | Dec 5 |
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 | 161 | 154 | 150 | 145 | 142 | 138 | 134 | 130 | 123 |
| 32°F | 182 | 176 | 171 | 166 | 162 | 159 | 155 | 150 | 144 |
| 28°F | 205 | 198 | 193 | 189 | 185 | 181 | 177 | 171 | 164 |
| 24°F | 226 | 220 | 215 | 210 | 207 | 203 | 200 | 194 | 187 |
| 20°F | 245 | 239 | 234 | 230 | 227 | 223 | 218 | 213 | 207 |
| 16°F | 263 | 256 | 252 | 248 | 244 | 239 | 236 | 232 | 225 |
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
- 7,758
- Cooling degree days, base 65°F
- 492
- Growing degree days, base 40°F
- 4,273
- Growing degree days, base 45°F
- 3,269
- Growing degree days, base 50°F
- 2,384
- Growing degree days, base 55°F
- 1,622
- Growing degree days, base 60°F
- 983
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,489 | 0 | 0 |
| February | 1,256 | 0 | 0 |
| March | 1,051 | 0 | 10 |
| April | 639 | 1 | 46 |
| May | 308 | 26 | 220 |
| June | 74 | 103 | 479 |
| July | 16 | 177 | 626 |
| August | 30 | 134 | 569 |
| September | 171 | 48 | 337 |
| October | 529 | 3 | 88 |
| November | 905 | 0 | 9 |
| December | 1,291 | 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 13.5 km from Eden. 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 USC00472839 (Fond Du Lac Wwtp). Public domain.