Richmond Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Tallulah. 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 2 and the first fall freeze around November 24, a growing season of about 271 days.
- Median at 36°F
- last March 14, first November 12
- Median at 32°F
- last March 2, first November 24
- Median at 28°F
- last February 13, first December 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 | Apr 3 | Mar 28 | Mar 23 | Mar 18 | Mar 14 | Mar 11 | Mar 7 | Mar 2 | Feb 24 |
| 32°F | Mar 21 | Mar 14 | Mar 9 | Mar 5 | Mar 2 | Feb 26 | Feb 20 | Feb 14 | Feb 3 |
| 28°F | Mar 10 | Mar 2 | Feb 25 | Feb 19 | Feb 13 | Feb 5 | Jan 31 | Jan 25 | Jan 14 |
| 24°F | Mar 2 | Feb 18 | Feb 9 | Feb 2 | Jan 30 | Jan 23 | Jan 16 | Jan 8 | Dec 28 |
| 20°F | Feb 16 | Feb 7 | Feb 1 | Jan 27 | Jan 20 | Jan 14 | Jan 9 | Jan 5 | Dec 28 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 29 | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 19 | Nov 23 | Dec 1 |
| 32°F | Nov 6 | Nov 12 | Nov 16 | Nov 21 | Nov 24 | Nov 29 | Dec 3 | Dec 7 | Dec 14 |
| 28°F | Nov 18 | Nov 26 | Dec 1 | Dec 5 | Dec 10 | Dec 17 | Dec 27 | Jan 2 | Jan 13 |
| 24°F | Dec 3 | Dec 10 | Dec 20 | Dec 28 | Jan 1 | Jan 6 | Jan 11 | Jan 19 | Feb 1 |
| 20°F | Dec 22 | Dec 30 | Jan 1 | Jan 6 | Jan 9 | Jan 15 | Jan 21 | Jan 29 | Feb 5 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 | 269 | 261 | 253 | 248 | 242 | 237 | 232 | 225 | 216 |
| 32°F | 301 | 289 | 281 | 276 | 271 | 265 | 259 | 252 | 241 |
| 28°F | 337 | 327 | 319 | 311 | 305 | 299 | 289 | 282 | 270 |
| 24°F | 365 | 365 | 354 | 344 | 336 | 331 | 323 | 312 | 301 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 356 | 343 | 329 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 |
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
- 99% of years
- 24°F or colder
- 80% of years
- 20°F or colder
- 39% of years
- 16°F or colder
- 9% 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
- 1,893
- Cooling degree days, base 65°F
- 2,856
- Growing degree days, base 40°F
- 10,150
- Growing degree days, base 45°F
- 8,433
- Growing degree days, base 50°F
- 6,824
- Growing degree days, base 55°F
- 5,353
- Growing degree days, base 60°F
- 4,025
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 504 | 8 | 112 |
| February | 363 | 12 | 148 |
| March | 206 | 49 | 333 |
| April | 65 | 141 | 528 |
| May | 5 | 328 | 787 |
| June | 0 | 496 | 946 |
| July | 0 | 589 | 1,054 |
| August | 0 | 590 | 1,055 |
| September | 2 | 419 | 867 |
| October | 58 | 176 | 585 |
| November | 247 | 36 | 270 |
| December | 444 | 13 | 139 |
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 1.3 km from Richmond. 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 USC00168923 (Tallulah). Public domain.