Sherman Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Tupelo Rgnl AP. 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 21 and the first fall freeze around November 10, a growing season of about 235 days.
- Median at 36°F
- last April 4, first November 1
- Median at 32°F
- last March 21, first November 10
- Median at 28°F
- last March 5, first November 23
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 19 | Apr 12 | Apr 9 | Apr 6 | Apr 4 | Apr 1 | Mar 29 | Mar 24 | Mar 17 |
| 32°F | Apr 6 | Apr 2 | Mar 30 | Mar 26 | Mar 21 | Mar 17 | Mar 13 | Mar 8 | Feb 28 |
| 28°F | Mar 24 | Mar 18 | Mar 14 | Mar 9 | Mar 5 | Feb 28 | Feb 26 | Feb 21 | Feb 12 |
| 24°F | Mar 13 | Mar 4 | Feb 27 | Feb 23 | Feb 18 | Feb 13 | Feb 7 | Jan 31 | Jan 24 |
| 20°F | Feb 28 | Feb 20 | Feb 13 | Feb 7 | Feb 1 | Jan 29 | Jan 24 | Jan 16 | Jan 8 |
| 16°F | Feb 14 | Feb 6 | Jan 31 | Jan 28 | Jan 24 | Jan 18 | Jan 14 | Jan 8 | Dec 31 |
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 20 | Oct 24 | Oct 27 | Oct 29 | Nov 1 | Nov 3 | Nov 5 | Nov 8 | Nov 14 |
| 32°F | Oct 29 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 17 | Nov 22 | Nov 28 |
| 28°F | Nov 6 | Nov 10 | Nov 14 | Nov 19 | Nov 23 | Nov 26 | Dec 1 | Dec 5 | Dec 13 |
| 24°F | Nov 15 | Nov 23 | Nov 27 | Dec 2 | Dec 7 | Dec 13 | Dec 20 | Dec 28 | Jan 5 |
| 20°F | Nov 29 | Dec 8 | Dec 17 | Dec 25 | Jan 1 | Jan 3 | Jan 8 | Jan 14 | Jan 23 |
| 16°F | Dec 16 | Dec 29 | Jan 1 | Jan 5 | Jan 9 | Jan 12 | Jan 16 | Jan 20 | Jan 30 |
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 | 233 | 226 | 220 | 216 | 211 | 208 | 203 | 198 | 192 |
| 32°F | 260 | 251 | 245 | 240 | 235 | 230 | 225 | 218 | 211 |
| 28°F | 289 | 279 | 273 | 267 | 262 | 257 | 252 | 246 | 238 |
| 24°F | 325 | 312 | 305 | 299 | 292 | 286 | 279 | 271 | 262 |
| 20°F | 361 | 346 | 338 | 332 | 324 | 317 | 310 | 302 | 292 |
| 16°F | 365 | 365 | 365 | 363 | 353 | 346 | 338 | 333 | 319 |
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
- 93% of years
- 16°F or colder
- 65% 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
- 2,727
- Cooling degree days, base 65°F
- 2,234
- Growing degree days, base 40°F
- 8,806
- Growing degree days, base 45°F
- 7,194
- Growing degree days, base 50°F
- 5,723
- Growing degree days, base 55°F
- 4,402
- Growing degree days, base 60°F
- 3,238
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 671 | 1 | 54 |
| February | 498 | 3 | 75 |
| March | 328 | 19 | 212 |
| April | 124 | 72 | 403 |
| May | 20 | 230 | 676 |
| June | 0 | 425 | 874 |
| July | 0 | 538 | 1,003 |
| August | 0 | 513 | 978 |
| September | 6 | 321 | 765 |
| October | 116 | 98 | 452 |
| November | 370 | 12 | 163 |
| December | 594 | 3 | 70 |
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 12.5 km from Sherman. 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 USW00093862 (Tupelo Rgnl AP). Public domain.