Pulaski Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Pulaski 2 E. 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 25 and the first fall freeze around October 17, a growing season of about 175 days.
- Median at 36°F
- last May 6, first October 8
- Median at 32°F
- last April 25, first October 17
- Median at 28°F
- last April 9, first October 28
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 24 | May 18 | May 14 | May 10 | May 6 | May 4 | Apr 30 | Apr 26 | Apr 21 |
| 32°F | May 15 | May 7 | May 3 | Apr 29 | Apr 25 | Apr 22 | Apr 19 | Apr 15 | Apr 9 |
| 28°F | Apr 30 | Apr 21 | Apr 17 | Apr 13 | Apr 9 | Apr 6 | Apr 3 | Mar 31 | Mar 25 |
| 24°F | Apr 10 | Apr 4 | Apr 1 | Mar 30 | Mar 27 | Mar 23 | Mar 19 | Mar 16 | Mar 11 |
| 20°F | Mar 31 | Mar 26 | Mar 22 | Mar 19 | Mar 15 | Mar 12 | Mar 7 | Mar 2 | Feb 23 |
| 16°F | Mar 22 | Mar 15 | Mar 11 | Mar 7 | Mar 2 | Feb 26 | Feb 20 | Feb 12 | Feb 3 |
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 | Sep 25 | Sep 30 | Oct 2 | Oct 5 | Oct 8 | Oct 11 | Oct 13 | Oct 16 | Oct 21 |
| 32°F | Oct 5 | Oct 9 | Oct 12 | Oct 15 | Oct 17 | Oct 20 | Oct 23 | Oct 27 | Nov 1 |
| 28°F | Oct 12 | Oct 18 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 11 |
| 24°F | Oct 24 | Oct 29 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 15 | Nov 19 | Nov 26 |
| 20°F | Nov 3 | Nov 9 | Nov 13 | Nov 17 | Nov 21 | Nov 25 | Nov 29 | Dec 4 | Dec 12 |
| 16°F | Nov 16 | Nov 23 | Nov 28 | Dec 1 | Dec 5 | Dec 10 | Dec 14 | Dec 21 | Jan 1 |
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 | 173 | 167 | 161 | 158 | 154 | 149 | 145 | 139 | 133 |
| 32°F | 197 | 189 | 183 | 179 | 175 | 171 | 165 | 161 | 155 |
| 28°F | 219 | 213 | 208 | 204 | 200 | 196 | 190 | 185 | 176 |
| 24°F | 246 | 239 | 233 | 228 | 224 | 220 | 216 | 210 | 205 |
| 20°F | 278 | 268 | 261 | 256 | 251 | 245 | 240 | 234 | 227 |
| 16°F | 310 | 300 | 292 | 285 | 279 | 272 | 266 | 259 | 251 |
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
- 5,079
- Cooling degree days, base 65°F
- 663
- Growing degree days, base 40°F
- 5,489
- Growing degree days, base 45°F
- 4,195
- Growing degree days, base 50°F
- 3,070
- Growing degree days, base 55°F
- 2,108
- Growing degree days, base 60°F
- 1,303
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 986 | 0 | 5 |
| February | 816 | 0 | 8 |
| March | 696 | 0 | 40 |
| April | 388 | 6 | 147 |
| May | 171 | 40 | 343 |
| June | 31 | 132 | 551 |
| July | 5 | 222 | 682 |
| August | 10 | 183 | 639 |
| September | 88 | 73 | 437 |
| October | 355 | 8 | 170 |
| November | 639 | 0 | 38 |
| December | 894 | 0 | 10 |
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 0.9 km from Pulaski. 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 USC00446955 (Pulaski 2 E). Public domain.