Eagle Lake Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Ft Kent. 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 23 and the first fall freeze around September 24, a growing season of about 121 days.
- Median at 36°F
- last June 4, first September 13
- Median at 32°F
- last May 23, first September 24
- Median at 28°F
- last May 9, first October 3
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 17 | Jun 13 | Jun 10 | Jun 7 | Jun 4 | Jun 2 | May 31 | May 28 | May 24 |
| 32°F | Jun 6 | Jun 2 | May 29 | May 26 | May 23 | May 20 | May 16 | May 12 | May 8 |
| 28°F | May 23 | May 17 | May 13 | May 11 | May 9 | May 6 | May 3 | Apr 30 | Apr 28 |
| 24°F | May 9 | May 5 | May 2 | Apr 30 | Apr 29 | Apr 26 | Apr 24 | Apr 21 | Apr 17 |
| 20°F | Apr 29 | Apr 25 | Apr 22 | Apr 20 | Apr 18 | Apr 15 | Apr 13 | Apr 9 | Apr 6 |
| 16°F | Apr 21 | Apr 17 | Apr 14 | Apr 12 | Apr 10 | Apr 7 | Apr 5 | Apr 3 | Apr 1 |
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 | Aug 31 | Sep 4 | Sep 7 | Sep 10 | Sep 13 | Sep 15 | Sep 18 | Sep 21 | Sep 25 |
| 32°F | Sep 11 | Sep 15 | Sep 19 | Sep 21 | Sep 24 | Sep 26 | Sep 29 | Oct 1 | Oct 5 |
| 28°F | Sep 21 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 9 | Oct 12 | Oct 17 |
| 24°F | Oct 1 | Oct 5 | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 23 | Oct 26 | Nov 1 |
| 20°F | Oct 13 | Oct 19 | Oct 23 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 7 | Nov 12 |
| 16°F | Oct 26 | Oct 31 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 23 |
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 | 116 | 111 | 106 | 103 | 100 | 95 | 91 | 86 | 79 |
| 32°F | 139 | 134 | 129 | 125 | 121 | 118 | 114 | 110 | 102 |
| 28°F | 166 | 159 | 155 | 151 | 147 | 144 | 140 | 136 | 128 |
| 24°F | 190 | 182 | 178 | 174 | 170 | 166 | 163 | 159 | 153 |
| 20°F | 211 | 206 | 201 | 197 | 193 | 190 | 186 | 182 | 174 |
| 16°F | 230 | 224 | 220 | 216 | 212 | 209 | 205 | 200 | 193 |
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
- 10,015
- Cooling degree days, base 65°F
- 149
- Growing degree days, base 40°F
- 2,978
- Growing degree days, base 45°F
- 2,142
- Growing degree days, base 50°F
- 1,431
- Growing degree days, base 55°F
- 848
- Growing degree days, base 60°F
- 412
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,771 | 0 | 0 |
| February | 1,541 | 0 | 0 |
| March | 1,366 | 0 | 1 |
| April | 887 | 0 | 4 |
| May | 487 | 4 | 94 |
| June | 204 | 27 | 280 |
| July | 72 | 64 | 457 |
| August | 108 | 43 | 400 |
| September | 331 | 11 | 173 |
| October | 718 | 0 | 20 |
| November | 1,041 | 0 | 1 |
| December | 1,490 | 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 22.2 km from Eagle Lake. 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 USC00172878 (Ft Kent). Public domain.