Peapack Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Somerville Somerset AP. 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 26 and the first fall freeze around October 18, a growing season of about 176 days.
- Median at 36°F
- last May 7, first October 7
- Median at 32°F
- last April 26, first October 18
- Median at 28°F
- last April 11, first October 30
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 23 | May 18 | May 14 | May 10 | May 7 | May 4 | Apr 30 | Apr 27 | Apr 23 |
| 32°F | May 13 | May 7 | May 2 | Apr 29 | Apr 26 | Apr 23 | Apr 20 | Apr 16 | Apr 11 |
| 28°F | Apr 28 | Apr 22 | Apr 18 | Apr 14 | Apr 11 | Apr 8 | Apr 4 | Apr 1 | Mar 28 |
| 24°F | Apr 13 | Apr 8 | Apr 4 | Apr 1 | Mar 30 | Mar 27 | Mar 23 | Mar 19 | Mar 14 |
| 20°F | Apr 1 | Mar 29 | Mar 24 | Mar 20 | Mar 17 | Mar 14 | Mar 10 | Mar 6 | Mar 1 |
| 16°F | Mar 20 | Mar 16 | Mar 12 | Mar 8 | Mar 5 | Mar 1 | Feb 27 | Feb 23 | Feb 14 |
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 27 | Oct 1 | Oct 3 | Oct 5 | Oct 7 | Oct 9 | Oct 12 | Oct 16 | Oct 21 |
| 32°F | Oct 5 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 28 | Nov 2 |
| 28°F | Oct 14 | Oct 19 | Oct 23 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 7 | Nov 13 |
| 24°F | Oct 26 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 30 |
| 20°F | Nov 7 | Nov 13 | Nov 17 | Nov 21 | Nov 26 | Nov 29 | Dec 2 | Dec 6 | Dec 14 |
| 16°F | Nov 18 | Nov 26 | Dec 1 | Dec 4 | Dec 8 | Dec 13 | Dec 19 | Dec 24 | Jan 1 |
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 | 173 | 166 | 161 | 157 | 152 | 148 | 144 | 139 | 133 |
| 32°F | 198 | 190 | 185 | 180 | 176 | 171 | 166 | 161 | 153 |
| 28°F | 223 | 216 | 212 | 207 | 202 | 198 | 192 | 186 | 179 |
| 24°F | 250 | 243 | 235 | 231 | 226 | 222 | 218 | 212 | 205 |
| 20°F | 277 | 268 | 262 | 257 | 251 | 246 | 242 | 236 | 228 |
| 16°F | 306 | 296 | 289 | 284 | 279 | 274 | 269 | 262 | 254 |
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
- 5,385
- Cooling degree days, base 65°F
- 859
- Growing degree days, base 40°F
- 5,532
- Growing degree days, base 45°F
- 4,294
- Growing degree days, base 50°F
- 3,215
- Growing degree days, base 55°F
- 2,285
- Growing degree days, base 60°F
- 1,497
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,086 | 0 | 1 |
| February | 909 | 0 | 3 |
| March | 772 | 0 | 18 |
| April | 427 | 7 | 116 |
| May | 178 | 41 | 334 |
| June | 28 | 163 | 585 |
| July | 1 | 299 | 762 |
| August | 4 | 246 | 707 |
| September | 71 | 94 | 473 |
| October | 352 | 11 | 174 |
| November | 633 | 0 | 35 |
| December | 925 | 0 | 6 |
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 10.4 km from Peapack. 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 USW00054785 (Somerville Somerset AP). Public domain.