Prairie County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Des Arc. 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 11 and the first fall freeze around November 14, a growing season of about 247 days.
- Median at 36°F
- last March 27, first November 3
- Median at 32°F
- last March 11, first November 14
- Median at 28°F
- last March 2, first November 26
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 15 | Apr 7 | Apr 3 | Mar 31 | Mar 27 | Mar 22 | Mar 18 | Mar 12 | Mar 7 |
| 32°F | Apr 1 | Mar 26 | Mar 20 | Mar 16 | Mar 11 | Mar 8 | Mar 5 | Mar 1 | Feb 23 |
| 28°F | Mar 19 | Mar 13 | Mar 9 | Mar 5 | Mar 2 | Feb 27 | Feb 22 | Feb 17 | Feb 9 |
| 24°F | Mar 10 | Mar 5 | Mar 1 | Feb 23 | Feb 18 | Feb 12 | Feb 6 | Jan 31 | Jan 22 |
| 20°F | Mar 1 | Feb 21 | Feb 13 | Feb 6 | Feb 2 | Jan 29 | Jan 23 | Jan 14 | Jan 4 |
| 16°F | Feb 22 | Feb 10 | Feb 3 | Jan 30 | Jan 25 | Jan 20 | Jan 14 | Jan 6 | Dec 29 |
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 20 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 14 | Nov 19 |
| 32°F | Oct 31 | Nov 3 | Nov 7 | Nov 10 | Nov 14 | Nov 18 | Nov 22 | Nov 27 | Dec 2 |
| 28°F | Nov 7 | Nov 12 | Nov 17 | Nov 21 | Nov 26 | Nov 30 | Dec 3 | Dec 10 | Dec 19 |
| 24°F | Nov 17 | Nov 25 | Nov 30 | Dec 4 | Dec 11 | Dec 17 | Dec 24 | Dec 31 | Jan 7 |
| 20°F | Dec 1 | Dec 11 | Dec 21 | Dec 25 | Dec 30 | Jan 3 | Jan 9 | Jan 14 | Jan 27 |
| 16°F | Dec 14 | Dec 24 | Dec 30 | Jan 2 | Jan 7 | Jan 12 | Jan 17 | Jan 26 | Feb 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 | 246 | 238 | 232 | 228 | 224 | 219 | 214 | 209 | 202 |
| 32°F | 271 | 264 | 258 | 252 | 247 | 242 | 235 | 229 | 221 |
| 28°F | 298 | 288 | 280 | 274 | 269 | 262 | 257 | 251 | 242 |
| 24°F | 333 | 321 | 310 | 303 | 297 | 291 | 284 | 275 | 263 |
| 20°F | 364 | 351 | 341 | 334 | 328 | 321 | 312 | 304 | 292 |
| 16°F | 365 | 365 | 365 | 362 | 353 | 344 | 337 | 330 | 316 |
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
- 99% of years
- 20°F or colder
- 92% of years
- 16°F or colder
- 63% 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
- 3,037
- Cooling degree days, base 65°F
- 2,232
- Growing degree days, base 40°F
- 8,580
- Growing degree days, base 45°F
- 7,023
- Growing degree days, base 50°F
- 5,606
- Growing degree days, base 55°F
- 4,332
- Growing degree days, base 60°F
- 3,205
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 752 | 1 | 32 |
| February | 562 | 2 | 60 |
| March | 367 | 15 | 189 |
| April | 135 | 72 | 396 |
| May | 23 | 231 | 673 |
| June | 0 | 443 | 892 |
| July | 0 | 549 | 1,014 |
| August | 0 | 516 | 981 |
| September | 10 | 302 | 742 |
| October | 131 | 89 | 431 |
| November | 396 | 12 | 151 |
| December | 661 | 1 | 45 |
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 17.1 km from Prairie 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 USC00031968 (Des Arc). Public domain.