Sheridan Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Dallas 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 16 and the first fall freeze around November 1, a growing season of about 199 days.
- Median at 36°F
- last May 6, first October 13
- Median at 32°F
- last April 16, first November 1
- Median at 28°F
- last March 7, first November 20
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 17 | May 13 | May 9 | May 6 | May 2 | Apr 29 | Apr 26 | Apr 19 |
| 32°F | May 5 | Apr 29 | Apr 25 | Apr 20 | Apr 16 | Apr 10 | Apr 4 | Mar 30 | Mar 21 |
| 28°F | Apr 8 | Mar 29 | Mar 22 | Mar 15 | Mar 7 | Feb 27 | Feb 21 | Feb 15 | Feb 2 |
| 24°F | Feb 27 | Feb 19 | Feb 11 | Feb 4 | Jan 29 | Jan 16 | Jan 6 | Dec 30 | Dec 14 |
| 20°F | Feb 10 | Jan 31 | Jan 18 | Jan 8 | Jan 1 | Dec 25 | Dec 18 | Dec 10 | Dec 2 |
| 16°F | Feb 5 | Jan 23 | Jan 10 | Jan 1 | Dec 24 | Dec 20 | Dec 16 | Dec 12 | Dec 4 |
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 29 | Oct 3 | Oct 6 | Oct 10 | Oct 13 | Oct 17 | Oct 22 | Oct 27 | Nov 1 |
| 32°F | Oct 13 | Oct 21 | Oct 25 | Oct 28 | Nov 1 | Nov 5 | Nov 9 | Nov 14 | Nov 22 |
| 28°F | Oct 31 | Nov 7 | Nov 11 | Nov 15 | Nov 20 | Nov 25 | Dec 1 | Dec 5 | Dec 15 |
| 24°F | Nov 14 | Nov 24 | Nov 30 | Dec 4 | Dec 9 | Dec 16 | Dec 23 | Dec 31 | Jan 14 |
| 20°F | Nov 25 | Dec 2 | Dec 8 | Dec 14 | Dec 22 | Dec 29 | Jan 3 | Jan 13 | Feb 1 |
| 16°F | Dec 2 | Dec 10 | Dec 14 | Dec 17 | Dec 22 | Dec 30 | Jan 2 | Jan 19 | Feb 4 |
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 | 184 | 175 | 170 | 164 | 159 | 155 | 150 | 145 | 136 |
| 32°F | 231 | 219 | 211 | 205 | 199 | 194 | 187 | 180 | 173 |
| 28°F | 297 | 284 | 273 | 265 | 258 | 250 | 243 | 233 | 220 |
| 24°F | 359 | 346 | 336 | 327 | 319 | 312 | 303 | 291 | 276 |
| 20°F | 365 | 365 | 365 | 365 | 357 | 348 | 341 | 332 | 319 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 363 | 345 |
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
- 93% of years
- 20°F or colder
- 52% of years
- 16°F or colder
- 18% 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
- 4,633
- Cooling degree days, base 65°F
- 294
- Growing degree days, base 40°F
- 4,973
- Growing degree days, base 45°F
- 3,501
- Growing degree days, base 50°F
- 2,317
- Growing degree days, base 55°F
- 1,406
- Growing degree days, base 60°F
- 736
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 747 | 0 | 4 |
| February | 613 | 0 | 6 |
| March | 567 | 0 | 25 |
| April | 437 | 1 | 72 |
| May | 266 | 9 | 216 |
| June | 146 | 26 | 330 |
| July | 30 | 101 | 536 |
| August | 27 | 108 | 546 |
| September | 96 | 47 | 401 |
| October | 339 | 3 | 156 |
| November | 593 | 0 | 22 |
| December | 770 | 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 18.8 km from Sheridan. 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 USC00352112 (Dallas 2 Ne). Public domain.