Rockingham County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Reidsville 2 Nw. 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 5 and the first fall freeze around November 2, a growing season of about 213 days.
- Median at 36°F
- last April 19, first October 24
- Median at 32°F
- last April 5, first November 2
- Median at 28°F
- last March 24, first November 13
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 8 | May 2 | Apr 27 | Apr 23 | Apr 19 | Apr 15 | Apr 12 | Apr 8 | Apr 4 |
| 32°F | Apr 21 | Apr 15 | Apr 10 | Apr 7 | Apr 5 | Apr 2 | Mar 30 | Mar 26 | Mar 20 |
| 28°F | Apr 8 | Apr 3 | Mar 31 | Mar 27 | Mar 24 | Mar 20 | Mar 16 | Mar 12 | Mar 6 |
| 24°F | Mar 28 | Mar 23 | Mar 19 | Mar 14 | Mar 11 | Mar 7 | Mar 3 | Feb 27 | Feb 19 |
| 20°F | Mar 19 | Mar 11 | Mar 6 | Mar 1 | Feb 26 | Feb 19 | Feb 13 | Feb 7 | Jan 31 |
| 16°F | Mar 7 | Feb 28 | Feb 19 | Feb 12 | Feb 7 | Feb 2 | Jan 29 | Jan 22 | Jan 13 |
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 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 29 | Nov 1 | Nov 5 |
| 32°F | Oct 21 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 7 | Nov 12 | Nov 17 |
| 28°F | Oct 31 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 16 | Nov 20 | Nov 25 | Dec 1 |
| 24°F | Nov 8 | Nov 13 | Nov 17 | Nov 23 | Nov 27 | Dec 1 | Dec 6 | Dec 12 | Dec 25 |
| 20°F | Nov 21 | Nov 29 | Dec 5 | Dec 10 | Dec 15 | Dec 22 | Dec 28 | Jan 3 | Jan 14 |
| 16°F | Dec 8 | Dec 17 | Dec 25 | Jan 1 | Jan 5 | Jan 10 | Jan 16 | Jan 23 | 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 | 209 | 203 | 198 | 193 | 188 | 184 | 179 | 173 | 166 |
| 32°F | 234 | 227 | 222 | 217 | 213 | 208 | 204 | 198 | 191 |
| 28°F | 261 | 252 | 246 | 242 | 237 | 233 | 227 | 222 | 214 |
| 24°F | 292 | 282 | 274 | 269 | 263 | 257 | 250 | 244 | 236 |
| 20°F | 327 | 314 | 307 | 302 | 297 | 291 | 283 | 274 | 263 |
| 16°F | 358 | 344 | 335 | 331 | 325 | 318 | 311 | 304 | 296 |
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
- 91% 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
- 3,825
- Cooling degree days, base 65°F
- 1,340
- Growing degree days, base 40°F
- 7,023
- Growing degree days, base 45°F
- 5,563
- Growing degree days, base 50°F
- 4,261
- Growing degree days, base 55°F
- 3,124
- Growing degree days, base 60°F
- 2,150
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 826 | 0 | 17 |
| February | 669 | 0 | 24 |
| March | 524 | 3 | 98 |
| April | 251 | 28 | 257 |
| May | 87 | 107 | 487 |
| June | 10 | 272 | 712 |
| July | 0 | 388 | 852 |
| August | 1 | 336 | 800 |
| September | 30 | 171 | 591 |
| October | 215 | 32 | 297 |
| November | 484 | 2 | 95 |
| December | 727 | 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 7.4 km from Rockingham 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 USC00317202 (Reidsville 2 Nw). Public domain.