Floyd County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Rome. 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 3, a growing season of about 217 days.
- Median at 36°F
- last April 13, first October 25
- Median at 32°F
- last April 1, first November 3
- Median at 28°F
- last March 18, 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 | May 1 | Apr 25 | Apr 21 | Apr 17 | Apr 13 | Apr 10 | Apr 6 | Apr 3 | Mar 30 |
| 32°F | Apr 19 | Apr 11 | Apr 7 | Apr 4 | Apr 1 | Mar 30 | Mar 25 | Mar 20 | Mar 13 |
| 28°F | Apr 5 | Mar 31 | Mar 27 | Mar 22 | Mar 18 | Mar 14 | Mar 8 | Mar 1 | Feb 24 |
| 24°F | Mar 26 | Mar 18 | Mar 13 | Mar 6 | Mar 2 | Feb 26 | Feb 20 | Feb 13 | Feb 3 |
| 20°F | Mar 12 | Mar 3 | Feb 26 | Feb 17 | Feb 11 | Feb 4 | Jan 31 | Jan 23 | Jan 13 |
| 16°F | Mar 2 | Feb 14 | Feb 6 | Feb 2 | Jan 28 | Jan 22 | Jan 16 | Jan 9 | Jan 1 |
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 13 | Oct 18 | Oct 21 | Oct 23 | Oct 25 | Oct 27 | Oct 30 | Nov 2 | Nov 6 |
| 32°F | Oct 22 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 12 | Nov 18 |
| 28°F | Oct 30 | Nov 3 | Nov 6 | Nov 10 | Nov 14 | Nov 17 | Nov 22 | Nov 28 | Dec 3 |
| 24°F | Nov 8 | Nov 15 | Nov 19 | Nov 25 | Dec 1 | Dec 3 | Dec 8 | Dec 20 | Dec 30 |
| 20°F | Nov 22 | Dec 1 | Dec 5 | Dec 12 | Dec 21 | Dec 28 | Jan 2 | Jan 9 | Jan 19 |
| 16°F | Dec 7 | Dec 17 | Dec 26 | Jan 1 | Jan 3 | Jan 9 | Jan 15 | Jan 22 | 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 | 214 | 207 | 202 | 197 | 193 | 188 | 184 | 180 | 172 |
| 32°F | 239 | 231 | 226 | 221 | 217 | 212 | 207 | 202 | 194 |
| 28°F | 271 | 260 | 253 | 246 | 239 | 234 | 230 | 223 | 214 |
| 24°F | 308 | 293 | 285 | 279 | 272 | 264 | 257 | 249 | 235 |
| 20°F | 346 | 334 | 324 | 315 | 306 | 299 | 292 | 284 | 275 |
| 16°F | 365 | 365 | 354 | 346 | 340 | 333 | 327 | 316 | 301 |
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
- 98% of years
- 16°F or colder
- 81% 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
- 3,248
- Cooling degree days, base 65°F
- 1,600
- Growing degree days, base 40°F
- 7,705
- Growing degree days, base 45°F
- 6,160
- Growing degree days, base 50°F
- 4,774
- Growing degree days, base 55°F
- 3,548
- Growing degree days, base 60°F
- 2,492
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 741 | 0 | 30 |
| February | 576 | 0 | 39 |
| March | 412 | 6 | 144 |
| April | 182 | 34 | 315 |
| May | 46 | 137 | 557 |
| June | 3 | 312 | 759 |
| July | 0 | 428 | 893 |
| August | 0 | 402 | 866 |
| September | 15 | 230 | 664 |
| October | 169 | 48 | 355 |
| November | 443 | 4 | 111 |
| December | 661 | 1 | 43 |
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 5.7 km from Floyd 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 USC00097600 (Rome). Public domain.