Sutton Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Gassaway. 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 April 20 and the first fall freeze around October 25, a growing season of about 185 days.
- Median at 36°F
- last May 2, first October 15
- Median at 32°F
- last April 20, first October 25
- Median at 28°F
- last April 9, first November 1
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 19 | May 13 | May 9 | May 5 | May 2 | Apr 29 | Apr 26 | Apr 22 | Apr 18 |
| 32°F | May 9 | May 2 | Apr 28 | Apr 23 | Apr 20 | Apr 18 | Apr 16 | Apr 13 | Apr 8 |
| 28°F | Apr 22 | Apr 17 | Apr 14 | Apr 12 | Apr 9 | Apr 6 | Apr 3 | Apr 1 | Mar 28 |
| 24°F | Apr 11 | Apr 6 | Apr 3 | Mar 31 | Mar 30 | Mar 26 | Mar 22 | Mar 18 | Mar 12 |
| 20°F | Mar 31 | Mar 27 | Mar 23 | Mar 19 | Mar 16 | Mar 13 | Mar 9 | Mar 4 | Feb 27 |
| 16°F | Mar 21 | Mar 15 | Mar 11 | Mar 6 | Mar 3 | Feb 28 | Feb 25 | Feb 17 | 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 | Oct 5 | Oct 8 | Oct 10 | Oct 13 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 28 |
| 32°F | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 27 | Oct 29 | Nov 1 | Nov 4 |
| 28°F | Oct 20 | Oct 25 | Oct 28 | Oct 31 | Nov 1 | Nov 4 | Nov 6 | Nov 10 | Nov 15 |
| 24°F | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 18 | Nov 23 | Nov 29 |
| 20°F | Nov 6 | Nov 11 | Nov 15 | Nov 20 | Nov 25 | Nov 28 | Dec 1 | Dec 6 | Dec 16 |
| 16°F | Nov 16 | Nov 24 | Nov 29 | Dec 2 | Dec 6 | Dec 12 | Dec 18 | Dec 23 | Dec 31 |
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 | 184 | 179 | 175 | 171 | 166 | 162 | 158 | 153 | 147 |
| 32°F | 204 | 197 | 192 | 188 | 185 | 181 | 177 | 171 | 163 |
| 28°F | 225 | 219 | 214 | 210 | 206 | 202 | 197 | 192 | 186 |
| 24°F | 251 | 243 | 237 | 232 | 228 | 224 | 220 | 215 | 209 |
| 20°F | 280 | 271 | 264 | 258 | 253 | 247 | 242 | 236 | 229 |
| 16°F | 306 | 297 | 291 | 285 | 279 | 273 | 267 | 260 | 252 |
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
- 4,949
- Cooling degree days, base 65°F
- 961
- Growing degree days, base 40°F
- 5,981
- Growing degree days, base 45°F
- 4,685
- Growing degree days, base 50°F
- 3,541
- Growing degree days, base 55°F
- 2,539
- Growing degree days, base 60°F
- 1,679
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,031 | 0 | 5 |
| February | 846 | 0 | 7 |
| March | 709 | 0 | 40 |
| April | 352 | 10 | 181 |
| May | 132 | 68 | 408 |
| June | 17 | 184 | 617 |
| July | 1 | 297 | 761 |
| August | 2 | 261 | 724 |
| September | 48 | 125 | 527 |
| October | 308 | 17 | 216 |
| November | 620 | 0 | 45 |
| December | 885 | 0 | 11 |
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 5 km from Sutton. 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 USC00463361 (Gassaway). Public domain.