Sharon Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Dresden. 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 3 and the first fall freeze around November 1, a growing season of about 212 days.
- Median at 36°F
- last April 15, first October 24
- Median at 32°F
- last April 3, first November 1
- Median at 28°F
- last March 23, first November 12
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 1 | Apr 25 | Apr 21 | Apr 18 | Apr 15 | Apr 12 | Apr 9 | Apr 4 | Mar 30 |
| 32°F | Apr 20 | Apr 13 | Apr 9 | Apr 6 | Apr 3 | Mar 31 | Mar 28 | Mar 23 | Mar 18 |
| 28°F | Apr 9 | Apr 3 | Mar 31 | Mar 27 | Mar 23 | Mar 19 | Mar 16 | Mar 10 | Mar 4 |
| 24°F | Mar 29 | Mar 22 | Mar 17 | Mar 13 | Mar 9 | Mar 5 | Mar 1 | Feb 26 | Feb 19 |
| 20°F | Mar 17 | Mar 10 | Mar 4 | Mar 1 | Feb 26 | Feb 22 | Feb 16 | Feb 11 | Feb 3 |
| 16°F | Mar 6 | Feb 28 | Feb 24 | Feb 18 | Feb 13 | Feb 7 | Feb 1 | Jan 28 | Jan 17 |
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 13 | Oct 17 | Oct 19 | Oct 22 | Oct 24 | Oct 26 | Oct 28 | Oct 31 | Nov 4 |
| 32°F | Oct 21 | Oct 25 | Oct 28 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 15 |
| 28°F | Oct 31 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 24 | Nov 29 |
| 24°F | Nov 7 | Nov 12 | Nov 16 | Nov 19 | Nov 23 | Nov 27 | Dec 1 | Dec 5 | Dec 12 |
| 20°F | Nov 15 | Nov 22 | Nov 27 | Dec 1 | Dec 4 | Dec 9 | Dec 13 | Dec 20 | Dec 28 |
| 16°F | Nov 27 | Dec 3 | Dec 9 | Dec 15 | Dec 22 | Dec 27 | Jan 1 | Jan 6 | Jan 16 |
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 | 211 | 204 | 199 | 194 | 191 | 187 | 183 | 179 | 172 |
| 32°F | 234 | 226 | 221 | 216 | 212 | 209 | 203 | 198 | 192 |
| 28°F | 258 | 251 | 245 | 240 | 234 | 230 | 225 | 221 | 213 |
| 24°F | 286 | 276 | 269 | 263 | 257 | 252 | 248 | 242 | 233 |
| 20°F | 312 | 302 | 294 | 288 | 283 | 276 | 271 | 264 | 254 |
| 16°F | 340 | 331 | 323 | 316 | 309 | 304 | 297 | 288 | 278 |
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
- 99% 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
- 3,899
- Cooling degree days, base 65°F
- 1,581
- Growing degree days, base 40°F
- 7,318
- Growing degree days, base 45°F
- 5,883
- Growing degree days, base 50°F
- 4,589
- Growing degree days, base 55°F
- 3,442
- Growing degree days, base 60°F
- 2,436
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 887 | 0 | 17 |
| February | 691 | 0 | 30 |
| March | 508 | 7 | 113 |
| April | 230 | 38 | 289 |
| May | 61 | 137 | 541 |
| June | 4 | 314 | 760 |
| July | 0 | 426 | 891 |
| August | 1 | 397 | 862 |
| September | 25 | 213 | 639 |
| October | 206 | 44 | 321 |
| November | 502 | 4 | 101 |
| December | 786 | 0 | 25 |
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 12 km from Sharon. 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 USC00402600 (Dresden). Public domain.