Powderly Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Paris. 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 14 and the first fall freeze around November 16, a growing season of about 247 days.
- Median at 36°F
- last March 28, first November 6
- Median at 32°F
- last March 14, first November 16
- Median at 28°F
- last March 1, first December 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 | Apr 16 | Apr 9 | Apr 4 | Apr 1 | Mar 28 | Mar 23 | Mar 19 | Mar 14 | Mar 6 |
| 32°F | Apr 2 | Mar 28 | Mar 22 | Mar 18 | Mar 14 | Mar 10 | Mar 5 | Mar 2 | Feb 24 |
| 28°F | Mar 21 | Mar 14 | Mar 9 | Mar 5 | Mar 1 | Feb 27 | Feb 23 | Feb 18 | Feb 9 |
| 24°F | Mar 12 | Mar 5 | Mar 1 | Feb 23 | Feb 17 | Feb 11 | Feb 4 | Jan 30 | Jan 21 |
| 20°F | Mar 1 | Feb 21 | Feb 12 | Feb 5 | Jan 31 | Jan 27 | Jan 19 | Jan 11 | Dec 30 |
| 16°F | Feb 18 | Feb 7 | Jan 31 | Jan 25 | Jan 20 | Jan 14 | Jan 6 | Dec 31 | Dec 20 |
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 22 | Oct 27 | Oct 31 | Nov 2 | Nov 6 | Nov 9 | Nov 12 | Nov 17 | Nov 23 |
| 32°F | Nov 1 | Nov 5 | Nov 9 | Nov 12 | Nov 16 | Nov 22 | Nov 28 | Dec 1 | Dec 6 |
| 28°F | Nov 10 | Nov 15 | Nov 21 | Nov 27 | Dec 1 | Dec 4 | Dec 8 | Dec 12 | Dec 21 |
| 24°F | Nov 20 | Nov 30 | Dec 5 | Dec 9 | Dec 16 | Dec 23 | Dec 28 | Jan 4 | Jan 12 |
| 20°F | Dec 7 | Dec 14 | Dec 22 | Dec 28 | Jan 1 | Jan 5 | Jan 12 | Jan 20 | Feb 3 |
| 16°F | Dec 12 | Dec 19 | Dec 27 | Jan 1 | Jan 6 | Jan 12 | Jan 18 | Jan 28 | Feb 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 | 248 | 240 | 234 | 229 | 223 | 218 | 212 | 206 | 197 |
| 32°F | 275 | 265 | 257 | 252 | 247 | 243 | 236 | 229 | 220 |
| 28°F | 305 | 295 | 287 | 281 | 274 | 269 | 263 | 256 | 245 |
| 24°F | 337 | 326 | 317 | 309 | 302 | 297 | 289 | 281 | 269 |
| 20°F | 365 | 358 | 347 | 340 | 333 | 326 | 317 | 307 | 296 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 355 | 345 | 334 | 322 |
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
- 98% of years
- 20°F or colder
- 86% of years
- 16°F or colder
- 52% 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
- 2,636
- Cooling degree days, base 65°F
- 2,652
- Growing degree days, base 40°F
- 9,326
- Growing degree days, base 45°F
- 7,711
- Growing degree days, base 50°F
- 6,223
- Growing degree days, base 55°F
- 4,880
- Growing degree days, base 60°F
- 3,689
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 672 | 1 | 47 |
| February | 487 | 4 | 86 |
| March | 311 | 23 | 234 |
| April | 117 | 84 | 425 |
| May | 19 | 258 | 704 |
| June | 1 | 483 | 933 |
| July | 0 | 629 | 1,094 |
| August | 0 | 624 | 1,089 |
| September | 7 | 385 | 828 |
| October | 91 | 136 | 515 |
| November | 333 | 21 | 201 |
| December | 598 | 3 | 67 |
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 15.5 km from Powderly. 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 USC00416794 (Paris). Public domain.