Conway Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Murfreesboro. 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 6 and the first fall freeze around November 1, a growing season of about 208 days.
- Median at 36°F
- last April 21, first October 24
- Median at 32°F
- last April 6, first November 1
- Median at 28°F
- last March 26, first November 10
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 6 | May 1 | Apr 27 | Apr 23 | Apr 21 | Apr 17 | Apr 14 | Apr 10 | Apr 4 |
| 32°F | Apr 23 | Apr 17 | Apr 13 | Apr 10 | Apr 6 | Apr 3 | Mar 31 | Mar 28 | Mar 23 |
| 28°F | Apr 9 | Apr 4 | Apr 1 | Mar 29 | Mar 26 | Mar 23 | Mar 21 | Mar 17 | Mar 11 |
| 24°F | Mar 29 | Mar 24 | Mar 20 | Mar 17 | Mar 14 | Mar 10 | Mar 5 | Feb 28 | Feb 20 |
| 20°F | Mar 18 | Mar 13 | Mar 7 | Mar 3 | Feb 28 | Feb 23 | Feb 16 | Feb 7 | Jan 31 |
| 16°F | Mar 5 | Feb 28 | Feb 22 | Feb 12 | Feb 5 | Jan 31 | Jan 28 | Jan 19 | Jan 9 |
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 15 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 29 | Nov 1 | Nov 4 |
| 32°F | Oct 20 | Oct 25 | Oct 28 | Oct 30 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 15 |
| 28°F | Oct 30 | Nov 2 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 18 | Nov 22 | Dec 1 |
| 24°F | Nov 7 | Nov 12 | Nov 17 | Nov 22 | Nov 27 | Dec 1 | Dec 5 | Dec 11 | Dec 23 |
| 20°F | Nov 21 | Nov 30 | Dec 4 | Dec 10 | Dec 17 | Dec 24 | Dec 31 | Jan 4 | Jan 14 |
| 16°F | Dec 6 | Dec 18 | Dec 26 | Dec 31 | Jan 4 | Jan 8 | Jan 14 | Jan 20 | 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 | 205 | 199 | 193 | 189 | 184 | 180 | 176 | 172 | 164 |
| 32°F | 227 | 221 | 216 | 212 | 208 | 204 | 199 | 195 | 187 |
| 28°F | 255 | 245 | 241 | 236 | 231 | 227 | 223 | 218 | 212 |
| 24°F | 291 | 279 | 271 | 265 | 260 | 254 | 248 | 242 | 234 |
| 20°F | 323 | 311 | 304 | 297 | 291 | 285 | 277 | 268 | 260 |
| 16°F | 362 | 347 | 336 | 330 | 323 | 314 | 307 | 302 | 291 |
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
- 99% of years
- 16°F or colder
- 90% 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
- 3,717
- Cooling degree days, base 65°F
- 1,386
- Growing degree days, base 40°F
- 7,129
- Growing degree days, base 45°F
- 5,652
- Growing degree days, base 50°F
- 4,341
- Growing degree days, base 55°F
- 3,195
- Growing degree days, base 60°F
- 2,210
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 800 | 0 | 23 |
| February | 647 | 1 | 29 |
| March | 538 | 3 | 90 |
| April | 249 | 30 | 259 |
| May | 84 | 108 | 489 |
| June | 8 | 279 | 721 |
| July | 0 | 400 | 865 |
| August | 1 | 338 | 803 |
| September | 22 | 186 | 613 |
| October | 201 | 37 | 313 |
| November | 470 | 3 | 98 |
| December | 697 | 1 | 38 |
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 13.4 km from Conway. 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 USC00315996 (Murfreesboro). Public domain.