Folkston Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Folkston 9 Sw. 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 26 and the first fall freeze around December 7, a growing season of about 285 days.
- Median at 36°F
- last March 13, first November 22
- Median at 32°F
- last February 26, first December 7
- Median at 28°F
- last February 3, first December 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 | Apr 3 | Mar 26 | Mar 21 | Mar 17 | Mar 13 | Mar 9 | Mar 4 | Feb 28 | Feb 18 |
| 32°F | Mar 21 | Mar 14 | Mar 7 | Mar 2 | Feb 26 | Feb 20 | Feb 13 | Feb 5 | Jan 29 |
| 28°F | Mar 6 | Feb 26 | Feb 17 | Feb 9 | Feb 3 | Jan 30 | Jan 22 | Jan 13 | Jan 3 |
| 24°F | Feb 23 | Feb 14 | Feb 4 | Jan 31 | Jan 25 | Jan 18 | Jan 12 | Jan 5 | Dec 30 |
| 20°F | Feb 12 | Feb 4 | Jan 31 | Jan 23 | Jan 16 | Jan 11 | Jan 6 | Jan 2 | Dec 25 |
| 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 11 | Nov 15 | Nov 19 | Nov 22 | Nov 26 | Dec 1 | Dec 6 | Dec 13 |
| 32°F | Nov 16 | Nov 24 | Nov 28 | Dec 3 | Dec 7 | Dec 11 | Dec 20 | Dec 30 | Jan 7 |
| 28°F | Nov 30 | Dec 6 | Dec 13 | Dec 21 | Dec 30 | Jan 2 | Jan 7 | Jan 15 | Jan 29 |
| 24°F | Dec 9 | Dec 22 | Dec 31 | Jan 3 | Jan 8 | Jan 13 | Jan 21 | Jan 29 | Feb 7 |
| 20°F | Dec 16 | Dec 29 | Jan 4 | Jan 9 | Jan 13 | Jan 19 | Jan 27 | Feb 2 | Feb 9 |
| 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 | 284 | 273 | 266 | 260 | 254 | 248 | 243 | 237 | 226 |
| 32°F | 320 | 308 | 300 | 292 | 285 | 279 | 272 | 264 | 252 |
| 28°F | 357 | 342 | 334 | 327 | 320 | 312 | 305 | 296 | 283 |
| 24°F | 365 | 365 | 365 | 362 | 354 | 346 | 337 | 328 | 314 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 360 | 340 |
| 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
- 100% of years
- 28°F or colder
- 92% of years
- 24°F or colder
- 61% of years
- 20°F or colder
- 26% of years
- 16°F or colder
- 6% 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
- 1,109
- Cooling degree days, base 65°F
- 3,048
- Growing degree days, base 40°F
- 11,077
- Growing degree days, base 45°F
- 9,284
- Growing degree days, base 50°F
- 7,545
- Growing degree days, base 55°F
- 5,904
- Growing degree days, base 60°F
- 4,395
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 324 | 19 | 217 |
| February | 212 | 26 | 254 |
| March | 122 | 79 | 429 |
| April | 30 | 171 | 591 |
| May | 3 | 347 | 809 |
| June | 0 | 495 | 945 |
| July | 0 | 575 | 1,040 |
| August | 0 | 560 | 1,025 |
| September | 0 | 438 | 888 |
| October | 22 | 235 | 678 |
| November | 126 | 72 | 402 |
| December | 270 | 33 | 267 |
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 15.1 km from Folkston. 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 USC00093465 (Folkston 9 Sw). Public domain.