Green County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Greensburg. 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 15 and the first fall freeze around October 24, a growing season of about 192 days.
- Median at 36°F
- last April 26, first October 15
- Median at 32°F
- last April 15, first October 24
- Median at 28°F
- last April 1, first November 4
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 12 | May 6 | May 2 | Apr 29 | Apr 26 | Apr 23 | Apr 20 | Apr 16 | Apr 12 |
| 32°F | May 2 | Apr 26 | Apr 21 | Apr 18 | Apr 15 | Apr 12 | Apr 8 | Apr 5 | Mar 31 |
| 28°F | Apr 18 | Apr 12 | Apr 7 | Apr 4 | Apr 1 | Mar 30 | Mar 27 | Mar 22 | Mar 16 |
| 24°F | Apr 6 | Apr 1 | Mar 28 | Mar 25 | Mar 21 | Mar 17 | Mar 12 | Mar 7 | Feb 28 |
| 20°F | Mar 26 | Mar 21 | Mar 16 | Mar 12 | Mar 7 | Mar 3 | Feb 28 | Feb 23 | Feb 13 |
| 16°F | Mar 17 | Mar 11 | Mar 5 | Mar 1 | Feb 25 | Feb 20 | Feb 12 | Feb 5 | Jan 30 |
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 2 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 17 | Oct 20 | Oct 23 | Oct 28 |
| 32°F | Oct 11 | Oct 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 30 | Nov 2 | Nov 6 |
| 28°F | Oct 21 | Oct 26 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 19 |
| 24°F | Nov 1 | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 22 | Nov 26 | Dec 1 |
| 20°F | Nov 11 | Nov 16 | Nov 20 | Nov 25 | Nov 28 | Dec 1 | Dec 4 | Dec 10 | Dec 19 |
| 16°F | Nov 22 | Nov 29 | Dec 4 | Dec 8 | Dec 14 | Dec 20 | Dec 25 | Jan 1 | Jan 7 |
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 | 191 | 184 | 179 | 175 | 171 | 167 | 163 | 158 | 151 |
| 32°F | 212 | 206 | 201 | 196 | 192 | 188 | 183 | 178 | 171 |
| 28°F | 236 | 229 | 224 | 219 | 215 | 211 | 208 | 202 | 194 |
| 24°F | 265 | 257 | 250 | 245 | 241 | 235 | 230 | 225 | 218 |
| 20°F | 296 | 285 | 277 | 272 | 267 | 262 | 256 | 249 | 241 |
| 16°F | 328 | 317 | 307 | 301 | 294 | 288 | 281 | 273 | 262 |
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
- 4,281
- Cooling degree days, base 65°F
- 1,354
- Growing degree days, base 40°F
- 6,806
- Growing degree days, base 45°F
- 5,419
- Growing degree days, base 50°F
- 4,184
- Growing degree days, base 55°F
- 3,091
- Growing degree days, base 60°F
- 2,151
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 927 | 0 | 16 |
| February | 739 | 0 | 21 |
| March | 578 | 4 | 83 |
| April | 284 | 23 | 235 |
| May | 88 | 110 | 488 |
| June | 7 | 277 | 720 |
| July | 0 | 389 | 854 |
| August | 1 | 353 | 817 |
| September | 33 | 171 | 588 |
| October | 249 | 26 | 269 |
| November | 557 | 1 | 70 |
| December | 817 | 0 | 24 |
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 4.7 km from Green County. 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 USC00153430 (Greensburg). Public domain.