Baldwin Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Franklin 3 Nw. 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 February 11 and the first fall freeze around December 8, a growing season of about 303 days.
- Median at 36°F
- last March 1, first November 22
- Median at 32°F
- last February 11, first December 8
- Median at 28°F
- last January 27, first December 31
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 | Mar 21 | Mar 15 | Mar 10 | Mar 6 | Mar 1 | Feb 26 | Feb 19 | Feb 13 | Feb 1 |
| 32°F | Mar 11 | Mar 2 | Feb 25 | Feb 18 | Feb 11 | Feb 4 | Jan 30 | Jan 23 | Jan 12 |
| 28°F | Feb 26 | Feb 15 | Feb 5 | Jan 31 | Jan 27 | Jan 21 | Jan 14 | Jan 4 | Dec 22 |
| 24°F | Feb 15 | Feb 2 | Jan 29 | Jan 23 | Jan 16 | Jan 10 | Jan 4 | Dec 30 | Dec 21 |
| 20°F | Feb 10 | Feb 2 | Jan 29 | Jan 25 | Jan 17 | Jan 13 | Jan 10 | Jan 7 | Jan 3 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 | Nov 5 | Nov 10 | Nov 14 | Nov 18 | Nov 22 | Nov 26 | Nov 30 | Dec 4 | Dec 12 |
| 32°F | Nov 15 | Nov 23 | Nov 29 | Dec 3 | Dec 8 | Dec 15 | Dec 23 | Jan 1 | Jan 9 |
| 28°F | Dec 1 | Dec 9 | Dec 17 | Dec 24 | Dec 31 | Jan 3 | Jan 9 | Jan 17 | Feb 1 |
| 24°F | Dec 16 | Dec 23 | Dec 29 | Jan 2 | Jan 7 | Jan 11 | Jan 18 | Jan 28 | Feb 5 |
| 20°F | Jan 1 | Jan 6 | Jan 8 | Jan 12 | Jan 15 | Jan 20 | Jan 27 | Feb 1 | Feb 7 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 | 300 | 287 | 279 | 272 | 266 | 260 | 254 | 247 | 238 |
| 32°F | 339 | 328 | 317 | 309 | 303 | 294 | 286 | 276 | 263 |
| 28°F | 365 | 365 | 357 | 348 | 340 | 334 | 327 | 317 | 303 |
| 24°F | 365 | 365 | 365 | 365 | 365 | 365 | 356 | 345 | 333 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 363 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 |
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
- 99% of years
- 28°F or colder
- 83% of years
- 24°F or colder
- 46% of years
- 20°F or colder
- 12% of years
- 16°F or colder
- 3% 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
- 1,333
- Cooling degree days, base 65°F
- 2,759
- Growing degree days, base 40°F
- 10,568
- Growing degree days, base 45°F
- 8,788
- Growing degree days, base 50°F
- 7,078
- Growing degree days, base 55°F
- 5,483
- Growing degree days, base 60°F
- 4,036
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 378 | 13 | 174 |
| February | 245 | 24 | 229 |
| March | 138 | 63 | 400 |
| April | 37 | 140 | 554 |
| May | 2 | 323 | 786 |
| June | 0 | 462 | 912 |
| July | 0 | 527 | 992 |
| August | 0 | 529 | 994 |
| September | 0 | 410 | 859 |
| October | 34 | 198 | 630 |
| November | 175 | 49 | 337 |
| December | 324 | 22 | 212 |
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 Baldwin. 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 USC00163313 (Franklin 3 Nw). Public domain.