Saucier Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Saucier Exp Forest. 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 7 and the first fall freeze around November 22, a growing season of about 260 days.
- Median at 36°F
- last March 21, first November 10
- Median at 32°F
- last March 7, first November 22
- Median at 28°F
- last February 19, first December 9
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 12 | Apr 4 | Mar 31 | Mar 26 | Mar 21 | Mar 17 | Mar 12 | Mar 8 | Mar 1 |
| 32°F | Mar 27 | Mar 20 | Mar 14 | Mar 11 | Mar 7 | Mar 2 | Feb 27 | Feb 21 | Feb 12 |
| 28°F | Mar 15 | Mar 7 | Mar 1 | Feb 25 | Feb 19 | Feb 12 | Feb 6 | Jan 31 | Jan 24 |
| 24°F | Mar 4 | Feb 25 | Feb 16 | Feb 7 | Feb 2 | Jan 30 | Jan 23 | Jan 15 | Jan 4 |
| 20°F | Feb 23 | Feb 9 | Feb 2 | Jan 29 | Jan 22 | Jan 17 | Jan 11 | Jan 5 | Dec 29 |
| 16°F | Feb 10 | Feb 1 | Jan 29 | Jan 22 | Jan 17 | Jan 13 | Jan 8 | Jan 3 | Dec 26 |
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 27 | Nov 1 | Nov 4 | Nov 6 | Nov 10 | Nov 13 | Nov 16 | Nov 21 | Nov 28 |
| 32°F | Nov 4 | Nov 10 | Nov 13 | Nov 18 | Nov 22 | Nov 26 | Dec 1 | Dec 5 | Dec 14 |
| 28°F | Nov 12 | Nov 22 | Nov 29 | Dec 3 | Dec 9 | Dec 16 | Dec 24 | Jan 1 | Jan 10 |
| 24°F | Dec 2 | Dec 11 | Dec 21 | Dec 28 | Jan 1 | Jan 5 | Jan 11 | Jan 19 | Jan 31 |
| 20°F | Dec 15 | Dec 26 | Jan 1 | Jan 4 | Jan 9 | Jan 15 | Jan 21 | Jan 30 | Feb 8 |
| 16°F | Dec 22 | Jan 1 | Jan 4 | Jan 9 | Jan 14 | Jan 19 | Jan 22 | Jan 30 | 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 | 263 | 252 | 245 | 239 | 233 | 228 | 222 | 216 | 207 |
| 32°F | 291 | 281 | 273 | 266 | 260 | 254 | 248 | 242 | 232 |
| 28°F | 329 | 317 | 307 | 299 | 293 | 286 | 279 | 272 | 259 |
| 24°F | 365 | 354 | 343 | 334 | 327 | 319 | 310 | 302 | 290 |
| 20°F | 365 | 365 | 365 | 365 | 358 | 348 | 339 | 330 | 316 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 359 | 336 |
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
- 99% of years
- 24°F or colder
- 89% of years
- 20°F or colder
- 58% of years
- 16°F or colder
- 24% 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
- 1,652
- Cooling degree days, base 65°F
- 2,355
- Growing degree days, base 40°F
- 9,861
- Growing degree days, base 45°F
- 8,110
- Growing degree days, base 50°F
- 6,447
- Growing degree days, base 55°F
- 4,914
- Growing degree days, base 60°F
- 3,544
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 440 | 6 | 138 |
| February | 302 | 11 | 175 |
| March | 181 | 38 | 337 |
| April | 61 | 97 | 487 |
| May | 6 | 261 | 719 |
| June | 0 | 411 | 861 |
| July | 0 | 488 | 953 |
| August | 0 | 482 | 947 |
| September | 1 | 361 | 810 |
| October | 50 | 156 | 572 |
| November | 224 | 34 | 283 |
| December | 386 | 11 | 166 |
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 7.7 km from Saucier. 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 USC00227840 (Saucier Exp Forest). Public domain.