Foard County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Copper Breaks SP. 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 1 and the first fall freeze around November 4, a growing season of about 217 days.
- Median at 36°F
- last April 13, first October 26
- Median at 32°F
- last April 1, first November 4
- Median at 28°F
- last March 14, first November 14
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 27 | Apr 23 | Apr 19 | Apr 17 | Apr 13 | Apr 9 | Apr 5 | Apr 2 | Mar 25 |
| 32°F | Apr 20 | Apr 14 | Apr 9 | Apr 5 | Apr 1 | Mar 28 | Mar 22 | Mar 16 | Mar 9 |
| 28°F | Apr 5 | Mar 31 | Mar 24 | Mar 18 | Mar 14 | Mar 10 | Mar 6 | Mar 1 | Feb 24 |
| 24°F | Mar 22 | Mar 14 | Mar 9 | Mar 5 | Mar 1 | Feb 27 | Feb 23 | Feb 18 | Feb 12 |
| 20°F | Mar 9 | Mar 3 | Feb 28 | Feb 23 | Feb 18 | Feb 14 | Feb 8 | Feb 1 | Jan 24 |
| 16°F | Mar 1 | Feb 22 | Feb 15 | Feb 7 | Feb 3 | Jan 30 | Jan 23 | Jan 15 | Jan 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 | Oct 12 | Oct 17 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 4 | Nov 10 |
| 32°F | Oct 18 | Oct 24 | Oct 28 | Nov 1 | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 21 |
| 28°F | Oct 27 | Nov 2 | Nov 7 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 28 | Dec 3 |
| 24°F | Nov 6 | Nov 13 | Nov 18 | Nov 22 | Nov 27 | Dec 1 | Dec 4 | Dec 8 | Dec 16 |
| 20°F | Nov 18 | Nov 24 | Dec 1 | Dec 4 | Dec 9 | Dec 15 | Dec 19 | Dec 26 | Jan 3 |
| 16°F | Nov 27 | Dec 4 | Dec 12 | Dec 18 | Dec 22 | Dec 28 | Jan 3 | Jan 10 | Jan 26 |
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 | 217 | 209 | 204 | 200 | 196 | 192 | 188 | 183 | 176 |
| 32°F | 244 | 234 | 228 | 222 | 217 | 212 | 207 | 200 | 191 |
| 28°F | 271 | 261 | 254 | 247 | 242 | 236 | 231 | 224 | 214 |
| 24°F | 295 | 286 | 278 | 273 | 268 | 263 | 256 | 248 | 239 |
| 20°F | 326 | 314 | 306 | 300 | 294 | 288 | 281 | 273 | 263 |
| 16°F | 356 | 343 | 335 | 330 | 322 | 314 | 307 | 300 | 290 |
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
- 93% 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
- 2,981
- Cooling degree days, base 65°F
- 2,559
- Growing degree days, base 40°F
- 8,933
- Growing degree days, base 45°F
- 7,359
- Growing degree days, base 50°F
- 5,926
- Growing degree days, base 55°F
- 4,652
- Growing degree days, base 60°F
- 3,533
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 716 | 0 | 28 |
| February | 561 | 1 | 50 |
| March | 331 | 21 | 218 |
| April | 139 | 71 | 392 |
| May | 23 | 269 | 712 |
| June | 0 | 494 | 943 |
| July | 0 | 645 | 1,110 |
| August | 0 | 608 | 1,072 |
| September | 13 | 348 | 784 |
| October | 127 | 93 | 441 |
| November | 398 | 10 | 148 |
| December | 671 | 1 | 30 |
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 15.6 km from Foard 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 USC00411995 (Copper Breaks SP). Public domain.