Mount Olive Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Mt Olive 6SE. 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 28 and the first fall freeze around November 7, a growing season of about 226 days.
- Median at 36°F
- last April 8, first October 29
- Median at 32°F
- last March 28, first November 7
- Median at 28°F
- last March 15, first November 18
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 21 | Apr 17 | Apr 13 | Apr 10 | Apr 8 | Apr 5 | Apr 2 | Mar 31 | Mar 25 |
| 32°F | Apr 10 | Apr 5 | Apr 2 | Mar 31 | Mar 28 | Mar 24 | Mar 20 | Mar 17 | Mar 10 |
| 28°F | Mar 31 | Mar 27 | Mar 21 | Mar 18 | Mar 15 | Mar 11 | Mar 6 | Mar 2 | Feb 25 |
| 24°F | Mar 20 | Mar 14 | Mar 9 | Mar 4 | Feb 28 | Feb 25 | Feb 18 | Feb 10 | Feb 2 |
| 20°F | Mar 5 | Feb 27 | Feb 18 | Feb 10 | Feb 5 | Jan 31 | Jan 27 | Jan 20 | Jan 10 |
| 16°F | Feb 17 | Feb 7 | Feb 1 | Jan 30 | Jan 26 | Jan 20 | Jan 14 | Jan 8 | Dec 31 |
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 17 | Oct 22 | Oct 25 | Oct 27 | Oct 29 | Nov 1 | Nov 2 | Nov 5 | Nov 10 |
| 32°F | Oct 27 | Oct 31 | Nov 2 | Nov 5 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 22 |
| 28°F | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 22 | Nov 27 | Dec 1 | Dec 9 |
| 24°F | Nov 14 | Nov 20 | Nov 26 | Dec 1 | Dec 4 | Dec 10 | Dec 17 | Dec 26 | Jan 3 |
| 20°F | Dec 1 | Dec 8 | Dec 15 | Dec 23 | Dec 29 | Jan 2 | Jan 7 | Jan 15 | Jan 24 |
| 16°F | Dec 15 | Dec 23 | Dec 30 | Jan 3 | Jan 9 | Jan 15 | Jan 19 | Jan 27 | Feb 2 |
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 | 223 | 216 | 211 | 208 | 205 | 201 | 197 | 192 | 185 |
| 32°F | 247 | 240 | 235 | 230 | 226 | 221 | 217 | 213 | 206 |
| 28°F | 281 | 271 | 263 | 257 | 250 | 245 | 241 | 235 | 228 |
| 24°F | 315 | 304 | 297 | 290 | 284 | 276 | 269 | 263 | 253 |
| 20°F | 349 | 338 | 332 | 326 | 319 | 312 | 306 | 297 | 285 |
| 16°F | 365 | 365 | 364 | 356 | 347 | 340 | 334 | 329 | 317 |
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
- 70% 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
- 3,119
- Cooling degree days, base 65°F
- 1,718
- Growing degree days, base 40°F
- 7,932
- Growing degree days, base 45°F
- 6,370
- Growing degree days, base 50°F
- 4,968
- Growing degree days, base 55°F
- 3,722
- Growing degree days, base 60°F
- 2,641
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 707 | 0 | 42 |
| February | 577 | 0 | 52 |
| March | 435 | 10 | 147 |
| April | 180 | 39 | 322 |
| May | 42 | 158 | 581 |
| June | 1 | 335 | 784 |
| July | 0 | 456 | 920 |
| August | 0 | 394 | 859 |
| September | 8 | 251 | 693 |
| October | 146 | 66 | 392 |
| November | 403 | 7 | 130 |
| December | 621 | 1 | 45 |
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 9.6 km from Mount Olive. 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 USC00315930 (Mt Olive 6SE). Public domain.