Ferron Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Ferron. 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 6 and the first fall freeze around October 10, a growing season of about 156 days.
- Median at 36°F
- last May 21, first October 1
- Median at 32°F
- last May 6, first October 10
- Median at 28°F
- last April 23, 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 9 | Jun 2 | May 29 | May 25 | May 21 | May 16 | May 13 | May 9 | May 3 |
| 32°F | May 27 | May 19 | May 14 | May 10 | May 6 | May 2 | Apr 30 | Apr 26 | Apr 22 |
| 28°F | May 11 | May 4 | Apr 30 | Apr 26 | Apr 23 | Apr 20 | Apr 17 | Apr 12 | Apr 6 |
| 24°F | Apr 26 | Apr 20 | Apr 16 | Apr 12 | Apr 8 | Apr 4 | Mar 31 | Mar 26 | Mar 17 |
| 20°F | Apr 10 | Apr 4 | Mar 30 | Mar 25 | Mar 20 | Mar 14 | Mar 9 | Mar 6 | Feb 28 |
| 16°F | Mar 23 | Mar 14 | Mar 8 | Mar 4 | Mar 1 | Feb 26 | Feb 23 | Feb 18 | Feb 10 |
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 23 | Sep 26 | Sep 29 | Oct 1 | Oct 4 | Oct 6 | Oct 9 | Oct 13 |
| 32°F | Sep 28 | Oct 1 | Oct 5 | Oct 7 | Oct 10 | Oct 13 | Oct 15 | Oct 18 | Oct 22 |
| 28°F | Oct 6 | Oct 10 | Oct 14 | Oct 17 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 4 |
| 24°F | Oct 15 | Oct 19 | Oct 23 | Oct 27 | Oct 31 | Nov 3 | Nov 6 | Nov 9 | Nov 13 |
| 20°F | Oct 25 | Oct 31 | Nov 3 | Nov 7 | Nov 10 | Nov 12 | Nov 15 | Nov 18 | Nov 22 |
| 16°F | Nov 3 | Nov 10 | Nov 13 | Nov 16 | Nov 20 | Nov 22 | Nov 25 | Nov 28 | Dec 4 |
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 | 152 | 145 | 140 | 136 | 131 | 126 | 122 | 115 | 108 |
| 32°F | 173 | 168 | 164 | 159 | 156 | 151 | 146 | 140 | 132 |
| 28°F | 198 | 191 | 185 | 181 | 177 | 173 | 168 | 164 | 156 |
| 24°F | 228 | 220 | 214 | 210 | 204 | 199 | 194 | 188 | 180 |
| 20°F | 257 | 248 | 242 | 237 | 232 | 227 | 222 | 216 | 207 |
| 16°F | 283 | 274 | 269 | 264 | 259 | 255 | 250 | 242 | 233 |
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
- 6,308
- Cooling degree days, base 65°F
- 755
- Growing degree days, base 40°F
- 4,960
- Growing degree days, base 45°F
- 3,844
- Growing degree days, base 50°F
- 2,871
- Growing degree days, base 55°F
- 2,036
- Growing degree days, base 60°F
- 1,330
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,226 | 0 | 0 |
| February | 937 | 0 | 0 |
| March | 740 | 0 | 14 |
| April | 502 | 1 | 74 |
| May | 244 | 24 | 271 |
| June | 50 | 148 | 548 |
| July | 4 | 299 | 761 |
| August | 6 | 222 | 680 |
| September | 105 | 60 | 410 |
| October | 450 | 2 | 109 |
| November | 840 | 0 | 4 |
| December | 1,206 | 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 Ferron. 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 USC00422798 (Ferron). Public domain.