Dyer Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Mountainburg 2 Ne. 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 9 and the first fall freeze around October 28, a growing season of about 201 days.
- Median at 36°F
- last April 23, first October 18
- Median at 32°F
- last April 9, first October 28
- Median at 28°F
- last March 28, first November 6
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 8 | May 3 | Apr 30 | Apr 26 | Apr 23 | Apr 19 | Apr 15 | Apr 12 | Apr 7 |
| 32°F | Apr 28 | Apr 21 | Apr 16 | Apr 13 | Apr 9 | Apr 6 | Apr 3 | Mar 30 | Mar 24 |
| 28°F | Apr 14 | Apr 7 | Apr 3 | Mar 31 | Mar 28 | Mar 24 | Mar 20 | Mar 14 | Mar 8 |
| 24°F | Apr 4 | Mar 29 | Mar 24 | Mar 19 | Mar 15 | Mar 11 | Mar 6 | Mar 1 | Feb 24 |
| 20°F | Mar 23 | Mar 16 | Mar 11 | Mar 6 | Mar 2 | Feb 27 | Feb 22 | Feb 15 | Feb 5 |
| 16°F | Mar 10 | Mar 4 | Feb 28 | Feb 23 | Feb 16 | Feb 10 | Feb 3 | Jan 30 | Jan 19 |
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 5 | Oct 9 | Oct 13 | Oct 16 | Oct 18 | Oct 21 | Oct 24 | Oct 27 | Nov 2 |
| 32°F | Oct 14 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 6 | Nov 12 |
| 28°F | Oct 23 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 14 | Nov 19 | Nov 25 |
| 24°F | Nov 1 | Nov 5 | Nov 10 | Nov 13 | Nov 18 | Nov 21 | Nov 27 | Dec 1 | Dec 6 |
| 20°F | Nov 10 | Nov 17 | Nov 22 | Nov 27 | Dec 1 | Dec 5 | Dec 9 | Dec 15 | Dec 23 |
| 16°F | Nov 21 | Dec 1 | Dec 6 | Dec 12 | Dec 19 | Dec 25 | Dec 31 | Jan 6 | Jan 15 |
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 | 201 | 194 | 188 | 183 | 179 | 174 | 170 | 164 | 156 |
| 32°F | 225 | 217 | 210 | 206 | 201 | 197 | 192 | 186 | 177 |
| 28°F | 250 | 239 | 232 | 227 | 222 | 218 | 214 | 208 | 202 |
| 24°F | 273 | 265 | 258 | 253 | 247 | 241 | 235 | 227 | 220 |
| 20°F | 303 | 292 | 284 | 277 | 272 | 266 | 261 | 254 | 245 |
| 16°F | 336 | 326 | 316 | 308 | 302 | 295 | 289 | 280 | 270 |
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
- 99% 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
- 3,733
- Cooling degree days, base 65°F
- 1,586
- Growing degree days, base 40°F
- 7,368
- Growing degree days, base 45°F
- 5,901
- Growing degree days, base 50°F
- 4,592
- Growing degree days, base 55°F
- 3,438
- Growing degree days, base 60°F
- 2,433
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 851 | 0 | 13 |
| February | 650 | 1 | 29 |
| March | 475 | 4 | 109 |
| April | 217 | 25 | 277 |
| May | 62 | 120 | 523 |
| June | 2 | 312 | 760 |
| July | 0 | 450 | 914 |
| August | 0 | 417 | 882 |
| September | 21 | 210 | 639 |
| October | 190 | 44 | 335 |
| November | 495 | 3 | 91 |
| December | 769 | 1 | 21 |
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 17.6 km from Dyer. 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 USC00035018 (Mountainburg 2 Ne). Public domain.