Wellington Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Wellington. 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 1 and the first fall freeze around November 4, a growing season of about 215 days.
- Median at 36°F
- last April 12, first October 28
- Median at 32°F
- last April 1, first November 4
- Median at 28°F
- last March 19, 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 | Apr 28 | Apr 23 | Apr 20 | Apr 16 | Apr 12 | Apr 9 | Apr 5 | Apr 2 | Mar 28 |
| 32°F | Apr 21 | Apr 13 | Apr 8 | Apr 5 | Apr 1 | Mar 30 | Mar 25 | Mar 21 | Mar 14 |
| 28°F | Apr 6 | Mar 31 | Mar 27 | Mar 23 | Mar 19 | Mar 15 | Mar 11 | Mar 6 | Feb 28 |
| 24°F | Mar 26 | Mar 19 | Mar 12 | Mar 8 | Mar 4 | Mar 1 | Feb 26 | Feb 21 | Feb 14 |
| 20°F | Mar 13 | Mar 5 | Mar 1 | Feb 26 | Feb 21 | Feb 17 | Feb 12 | Feb 6 | Jan 29 |
| 16°F | Mar 3 | Feb 25 | Feb 19 | Feb 14 | Feb 8 | Feb 2 | Jan 28 | Jan 19 | Jan 6 |
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 16 | Oct 20 | Oct 23 | Oct 26 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 8 |
| 32°F | Oct 22 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 17 |
| 28°F | Oct 30 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 23 | Nov 28 |
| 24°F | Nov 6 | Nov 12 | Nov 17 | Nov 21 | Nov 25 | Nov 28 | Dec 1 | Dec 5 | Dec 12 |
| 20°F | Nov 16 | Nov 23 | Nov 28 | Dec 1 | Dec 5 | Dec 12 | Dec 17 | Dec 22 | Dec 31 |
| 16°F | Nov 28 | Dec 4 | Dec 10 | Dec 17 | Dec 22 | Dec 28 | Jan 3 | Jan 10 | Jan 24 |
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 | 216 | 210 | 205 | 201 | 197 | 193 | 189 | 183 | 176 |
| 32°F | 237 | 229 | 224 | 219 | 215 | 211 | 206 | 200 | 193 |
| 28°F | 262 | 254 | 249 | 243 | 239 | 234 | 228 | 222 | 213 |
| 24°F | 287 | 280 | 273 | 268 | 264 | 258 | 253 | 246 | 236 |
| 20°F | 319 | 309 | 301 | 295 | 289 | 282 | 277 | 270 | 260 |
| 16°F | 353 | 340 | 331 | 322 | 316 | 309 | 303 | 292 | 279 |
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
- 95% 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
- 2,950
- Cooling degree days, base 65°F
- 2,399
- Growing degree days, base 40°F
- 8,816
- Growing degree days, base 45°F
- 7,233
- Growing degree days, base 50°F
- 5,794
- Growing degree days, base 55°F
- 4,510
- Growing degree days, base 60°F
- 3,378
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 711 | 0 | 26 |
| February | 542 | 1 | 59 |
| March | 341 | 17 | 210 |
| April | 131 | 74 | 404 |
| May | 26 | 242 | 681 |
| June | 1 | 465 | 915 |
| July | 0 | 601 | 1,066 |
| August | 0 | 569 | 1,034 |
| September | 7 | 336 | 778 |
| October | 115 | 88 | 447 |
| November | 399 | 6 | 144 |
| December | 677 | 0 | 32 |
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 1.6 km from Wellington. 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 USC00419565 (Wellington). Public domain.