Pulaski County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Winamac 2SSE. 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 18, a growing season of about 173 days.
- Median at 36°F
- last May 5, first October 7
- Median at 32°F
- last April 25, first October 18
- Median at 28°F
- last April 14, first October 29
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 23 | May 16 | May 13 | May 8 | May 5 | May 2 | Apr 29 | Apr 26 | Apr 22 |
| 32°F | May 11 | May 5 | May 1 | Apr 28 | Apr 25 | Apr 22 | Apr 19 | Apr 15 | Apr 11 |
| 28°F | Apr 27 | Apr 22 | Apr 18 | Apr 16 | Apr 14 | Apr 11 | Apr 7 | Apr 4 | Mar 31 |
| 24°F | Apr 16 | Apr 12 | Apr 7 | Apr 5 | Apr 2 | Mar 31 | Mar 28 | Mar 24 | Mar 19 |
| 20°F | Apr 7 | Apr 2 | Mar 31 | Mar 27 | Mar 24 | Mar 20 | Mar 16 | Mar 12 | Mar 6 |
| 16°F | Mar 29 | Mar 24 | Mar 19 | Mar 16 | Mar 13 | Mar 9 | Mar 5 | Mar 1 | Feb 23 |
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 24 | Sep 29 | Oct 1 | Oct 4 | Oct 7 | Oct 9 | Oct 12 | Oct 15 | Oct 20 |
| 32°F | Oct 1 | Oct 8 | Oct 12 | Oct 15 | Oct 18 | Oct 21 | Oct 23 | Oct 26 | Oct 31 |
| 28°F | Oct 16 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Oct 31 | Nov 2 | Nov 5 | Nov 11 |
| 24°F | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 16 | Nov 21 | Nov 27 |
| 20°F | Nov 6 | Nov 10 | Nov 14 | Nov 17 | Nov 21 | Nov 25 | Nov 28 | Dec 2 | Dec 8 |
| 16°F | Nov 11 | Nov 19 | Nov 25 | Nov 28 | Dec 1 | Dec 3 | Dec 7 | Dec 13 | Dec 21 |
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 | 171 | 165 | 161 | 157 | 153 | 148 | 145 | 140 | 133 |
| 32°F | 193 | 187 | 182 | 177 | 173 | 169 | 166 | 161 | 153 |
| 28°F | 218 | 210 | 205 | 201 | 198 | 194 | 189 | 184 | 177 |
| 24°F | 243 | 235 | 230 | 225 | 221 | 217 | 213 | 208 | 201 |
| 20°F | 266 | 258 | 252 | 247 | 242 | 238 | 233 | 227 | 219 |
| 16°F | 287 | 278 | 273 | 268 | 263 | 258 | 252 | 246 | 239 |
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
- 6,217
- Cooling degree days, base 65°F
- 819
- Growing degree days, base 40°F
- 5,280
- Growing degree days, base 45°F
- 4,132
- Growing degree days, base 50°F
- 3,113
- Growing degree days, base 55°F
- 2,217
- Growing degree days, base 60°F
- 1,451
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,266 | 0 | 1 |
| February | 1,056 | 0 | 2 |
| March | 849 | 1 | 28 |
| April | 472 | 7 | 114 |
| May | 192 | 62 | 349 |
| June | 32 | 183 | 602 |
| July | 5 | 255 | 715 |
| August | 10 | 203 | 659 |
| September | 98 | 93 | 448 |
| October | 387 | 14 | 168 |
| November | 749 | 0 | 27 |
| December | 1,100 | 0 | 3 |
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 Pulaski 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 USC00129670 (Winamac 2SSE). Public domain.