Buchanan Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Carrollton. 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 28 and the first fall freeze around November 5, a growing season of about 222 days.
- Median at 36°F
- last April 8, first October 26
- Median at 32°F
- last March 28, first November 5
- Median at 28°F
- last March 15, first November 16
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 26 | Apr 20 | Apr 16 | Apr 13 | Apr 8 | Apr 5 | Apr 2 | Mar 30 | Mar 24 |
| 32°F | Apr 12 | Apr 6 | Apr 2 | Mar 31 | Mar 28 | Mar 24 | Mar 20 | Mar 16 | Mar 7 |
| 28°F | Mar 31 | Mar 26 | Mar 22 | Mar 18 | Mar 15 | Mar 10 | Mar 6 | Feb 28 | Feb 20 |
| 24°F | Mar 21 | Mar 14 | Mar 9 | Mar 4 | Feb 28 | Feb 23 | Feb 16 | Feb 7 | Jan 29 |
| 20°F | Mar 9 | Mar 1 | Feb 23 | Feb 15 | Feb 7 | Feb 1 | Jan 28 | Jan 19 | Jan 10 |
| 16°F | Mar 1 | Feb 13 | Feb 4 | Jan 31 | Jan 26 | Jan 21 | Jan 16 | Jan 9 | Dec 30 |
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 14 | Oct 18 | Oct 21 | Oct 24 | Oct 26 | Oct 29 | Oct 31 | Nov 3 | Nov 8 |
| 32°F | Oct 23 | Oct 28 | Oct 31 | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 16 | Nov 22 |
| 28°F | Nov 1 | Nov 5 | Nov 9 | Nov 13 | Nov 16 | Nov 20 | Nov 26 | Dec 1 | Dec 7 |
| 24°F | Nov 9 | Nov 16 | Nov 22 | Nov 28 | Dec 1 | Dec 6 | Dec 13 | Dec 24 | Jan 1 |
| 20°F | Nov 25 | Dec 2 | Dec 9 | Dec 18 | Dec 26 | Jan 1 | Jan 4 | Jan 11 | Jan 21 |
| 16°F | Dec 9 | Dec 20 | Dec 28 | Jan 1 | Jan 5 | Jan 9 | Jan 15 | Jan 21 | Feb 1 |
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 | 220 | 213 | 208 | 204 | 200 | 195 | 191 | 185 | 178 |
| 32°F | 248 | 239 | 233 | 228 | 222 | 218 | 214 | 209 | 202 |
| 28°F | 278 | 269 | 261 | 255 | 249 | 243 | 238 | 233 | 224 |
| 24°F | 318 | 304 | 296 | 288 | 281 | 274 | 267 | 258 | 246 |
| 20°F | 349 | 337 | 330 | 322 | 314 | 306 | 300 | 290 | 278 |
| 16°F | 365 | 365 | 358 | 348 | 340 | 333 | 327 | 317 | 305 |
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
- 96% of years
- 16°F or colder
- 78% 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
- 2,992
- Cooling degree days, base 65°F
- 1,688
- Growing degree days, base 40°F
- 7,997
- Growing degree days, base 45°F
- 6,407
- Growing degree days, base 50°F
- 4,974
- Growing degree days, base 55°F
- 3,706
- Growing degree days, base 60°F
- 2,612
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 695 | 0 | 39 |
| February | 524 | 1 | 57 |
| March | 375 | 8 | 165 |
| April | 159 | 37 | 337 |
| May | 35 | 157 | 588 |
| June | 1 | 338 | 787 |
| July | 0 | 443 | 908 |
| August | 0 | 414 | 879 |
| September | 11 | 236 | 675 |
| October | 154 | 49 | 369 |
| November | 417 | 5 | 118 |
| December | 623 | 1 | 53 |
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 25 km from Buchanan. 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 USC00091640 (Carrollton). Public domain.