Martin Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Prestonsburg 3WSW. 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 April 23 and the first fall freeze around October 23, a growing season of about 183 days.
- Median at 36°F
- last May 4, first October 13
- Median at 32°F
- last April 23, first October 23
- Median at 28°F
- last April 9, first November 1
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 | May 19 | May 13 | May 9 | May 7 | May 4 | Apr 30 | Apr 27 | Apr 23 | Apr 18 |
| 32°F | May 10 | May 4 | Apr 30 | Apr 26 | Apr 23 | Apr 21 | Apr 17 | Apr 13 | Apr 8 |
| 28°F | Apr 27 | Apr 22 | Apr 18 | Apr 14 | Apr 9 | Apr 6 | Apr 3 | Mar 31 | Mar 25 |
| 24°F | Apr 14 | Apr 8 | Apr 4 | Apr 1 | Mar 30 | Mar 26 | Mar 21 | Mar 16 | Mar 9 |
| 20°F | Apr 4 | Mar 30 | Mar 24 | Mar 19 | Mar 16 | Mar 12 | Mar 6 | Feb 28 | Feb 22 |
| 16°F | Mar 25 | Mar 18 | Mar 12 | Mar 6 | Mar 2 | Feb 26 | Feb 19 | Feb 13 | Feb 4 |
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 1 | Oct 5 | Oct 8 | Oct 11 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 25 |
| 32°F | Oct 8 | Oct 14 | Oct 18 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Oct 31 | Nov 4 |
| 28°F | Oct 19 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 13 |
| 24°F | Oct 29 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 23 |
| 20°F | Nov 5 | Nov 9 | Nov 13 | Nov 16 | Nov 19 | Nov 23 | Nov 27 | Dec 2 | Dec 11 |
| 16°F | Nov 13 | Nov 18 | Nov 24 | Nov 30 | Dec 4 | Dec 10 | Dec 18 | Dec 25 | Jan 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 | 181 | 175 | 171 | 167 | 163 | 159 | 155 | 150 | 142 |
| 32°F | 201 | 195 | 190 | 186 | 183 | 179 | 174 | 169 | 162 |
| 28°F | 226 | 218 | 212 | 207 | 203 | 199 | 194 | 189 | 182 |
| 24°F | 252 | 241 | 235 | 229 | 225 | 221 | 216 | 211 | 203 |
| 20°F | 280 | 269 | 263 | 258 | 252 | 246 | 241 | 234 | 225 |
| 16°F | 313 | 301 | 293 | 287 | 280 | 274 | 266 | 259 | 247 |
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
- 100% of years
- 16°F or colder
- 100% 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
- 4,705
- Cooling degree days, base 65°F
- 1,022
- Growing degree days, base 40°F
- 6,119
- Growing degree days, base 45°F
- 4,781
- Growing degree days, base 50°F
- 3,611
- Growing degree days, base 55°F
- 2,603
- Growing degree days, base 60°F
- 1,747
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 985 | 0 | 5 |
| February | 792 | 0 | 6 |
| March | 646 | 0 | 39 |
| April | 331 | 15 | 191 |
| May | 111 | 68 | 426 |
| June | 8 | 193 | 636 |
| July | 0 | 313 | 778 |
| August | 2 | 277 | 741 |
| September | 54 | 137 | 534 |
| October | 304 | 19 | 213 |
| November | 613 | 0 | 38 |
| December | 860 | 0 | 5 |
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 11.3 km from Martin. 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 USC00156563 (Prestonsburg 3WSW). Public domain.