Nicholson Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Picayune. 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 9 and the first fall freeze around November 18, a growing season of about 255 days.
- Median at 36°F
- last March 26, first November 7
- Median at 32°F
- last March 9, first November 18
- Median at 28°F
- last February 24, first December 3
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 16 | Apr 7 | Apr 3 | Mar 30 | Mar 26 | Mar 21 | Mar 16 | Mar 10 | Mar 3 |
| 32°F | Mar 31 | Mar 25 | Mar 19 | Mar 13 | Mar 9 | Mar 4 | Feb 28 | Feb 24 | Feb 17 |
| 28°F | Mar 16 | Mar 9 | Mar 4 | Feb 28 | Feb 24 | Feb 18 | Feb 12 | Feb 4 | Jan 27 |
| 24°F | Mar 4 | Feb 26 | Feb 17 | Feb 9 | Feb 3 | Jan 30 | Jan 21 | Jan 13 | Dec 31 |
| 20°F | Feb 24 | Feb 10 | Feb 2 | Jan 29 | Jan 22 | Jan 16 | Jan 10 | Jan 3 | Dec 26 |
| 16°F | Feb 11 | Feb 2 | Jan 29 | Jan 24 | Jan 16 | Jan 10 | Jan 4 | Dec 31 | Dec 24 |
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 24 | Oct 29 | Nov 1 | Nov 5 | Nov 7 | Nov 11 | Nov 15 | Nov 19 | Nov 27 |
| 32°F | Nov 3 | Nov 7 | Nov 11 | Nov 15 | Nov 18 | Nov 23 | Nov 29 | Dec 3 | Dec 11 |
| 28°F | Nov 11 | Nov 17 | Nov 24 | Nov 30 | Dec 3 | Dec 7 | Dec 15 | Dec 28 | Jan 7 |
| 24°F | Nov 26 | Dec 2 | Dec 8 | Dec 17 | Dec 26 | Jan 1 | Jan 6 | Jan 14 | Jan 29 |
| 20°F | Dec 9 | Dec 19 | Dec 28 | Jan 1 | Jan 5 | Jan 12 | Jan 19 | Jan 26 | Feb 6 |
| 16°F | Dec 18 | Dec 27 | Jan 1 | Jan 5 | Jan 11 | Jan 17 | Jan 24 | Jan 31 | Feb 8 |
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 | 256 | 246 | 238 | 231 | 226 | 221 | 215 | 209 | 202 |
| 32°F | 287 | 276 | 267 | 261 | 255 | 249 | 242 | 235 | 226 |
| 28°F | 322 | 310 | 303 | 293 | 286 | 279 | 273 | 265 | 254 |
| 24°F | 364 | 345 | 335 | 329 | 321 | 313 | 306 | 297 | 285 |
| 20°F | 365 | 365 | 365 | 365 | 356 | 347 | 337 | 328 | 314 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 359 | 339 |
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
- 90% of years
- 20°F or colder
- 60% of years
- 16°F or colder
- 25% 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
- 1,820
- Cooling degree days, base 65°F
- 2,351
- Growing degree days, base 40°F
- 9,700
- Growing degree days, base 45°F
- 7,962
- Growing degree days, base 50°F
- 6,325
- Growing degree days, base 55°F
- 4,831
- Growing degree days, base 60°F
- 3,501
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 475 | 6 | 119 |
| February | 341 | 9 | 146 |
| March | 205 | 33 | 311 |
| April | 77 | 100 | 474 |
| May | 10 | 253 | 708 |
| June | 0 | 408 | 858 |
| July | 0 | 496 | 961 |
| August | 0 | 496 | 961 |
| September | 2 | 361 | 808 |
| October | 62 | 151 | 556 |
| November | 244 | 27 | 258 |
| December | 403 | 13 | 165 |
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 6.7 km from Nicholson. 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 USC00226921 (Picayune). Public domain.