Rainsville Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Ft Payne. 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 March 29 and the first fall freeze around November 8, a growing season of about 225 days.
- Median at 36°F
- last April 10, first October 31
- Median at 32°F
- last March 29, first November 8
- Median at 28°F
- last March 14, first November 20
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 26 | Apr 21 | Apr 17 | Apr 14 | Apr 10 | Apr 6 | Apr 3 | Mar 30 | Mar 24 |
| 32°F | Apr 16 | Apr 10 | Apr 5 | Apr 2 | Mar 29 | Mar 25 | Mar 20 | Mar 16 | Mar 7 |
| 28°F | Apr 5 | Mar 29 | Mar 23 | Mar 18 | Mar 14 | Mar 9 | Mar 3 | Feb 26 | Feb 18 |
| 24°F | Mar 19 | Mar 12 | Mar 6 | Mar 1 | Feb 25 | Feb 19 | Feb 14 | Feb 7 | Jan 28 |
| 20°F | Mar 9 | Feb 28 | Feb 22 | Feb 14 | Feb 6 | Feb 1 | Jan 29 | Jan 21 | Jan 11 |
| 16°F | Feb 25 | Feb 11 | Feb 3 | Jan 31 | Jan 27 | Jan 22 | Jan 17 | Jan 11 | Jan 2 |
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 19 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 4 | Nov 8 | Nov 13 |
| 32°F | Oct 26 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 21 | Nov 29 |
| 28°F | Nov 4 | Nov 8 | Nov 13 | Nov 17 | Nov 20 | Nov 26 | Dec 1 | Dec 4 | Dec 12 |
| 24°F | Nov 15 | Nov 20 | Nov 26 | Dec 1 | Dec 5 | Dec 10 | Dec 17 | Dec 25 | Jan 1 |
| 20°F | Nov 27 | Dec 6 | Dec 13 | Dec 20 | Dec 26 | Jan 1 | Jan 3 | Jan 10 | Jan 18 |
| 16°F | Dec 13 | Dec 22 | Dec 29 | Jan 2 | Jan 6 | Jan 11 | Jan 15 | Jan 21 | Jan 31 |
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 | 226 | 218 | 212 | 208 | 203 | 197 | 192 | 187 | 180 |
| 32°F | 256 | 244 | 236 | 230 | 225 | 220 | 215 | 209 | 201 |
| 28°F | 285 | 273 | 267 | 260 | 254 | 248 | 240 | 234 | 224 |
| 24°F | 317 | 305 | 298 | 290 | 284 | 277 | 271 | 263 | 253 |
| 20°F | 347 | 336 | 329 | 321 | 315 | 308 | 302 | 292 | 279 |
| 16°F | 365 | 363 | 353 | 345 | 338 | 334 | 328 | 319 | 305 |
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
- 96% of years
- 16°F or colder
- 81% 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
- 2,922
- Cooling degree days, base 65°F
- 1,940
- Growing degree days, base 40°F
- 8,355
- Growing degree days, base 45°F
- 6,771
- Growing degree days, base 50°F
- 5,326
- Growing degree days, base 55°F
- 4,028
- Growing degree days, base 60°F
- 2,900
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 718 | 0 | 42 |
| February | 530 | 2 | 62 |
| March | 359 | 10 | 184 |
| April | 158 | 53 | 359 |
| May | 38 | 183 | 611 |
| June | 1 | 365 | 814 |
| July | 0 | 477 | 942 |
| August | 0 | 456 | 921 |
| September | 9 | 301 | 742 |
| October | 116 | 84 | 439 |
| November | 378 | 8 | 150 |
| December | 616 | 1 | 60 |
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 12.9 km from Rainsville. 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 USC00013043 (Ft Payne). Public domain.