Como Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Senatobia. 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 20 and the first fall freeze around November 4, a growing season of about 229 days.
- Median at 36°F
- last April 2, first October 27
- Median at 32°F
- last March 20, first November 4
- Median at 28°F
- last March 9, first November 16
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 17 | Apr 11 | Apr 8 | Apr 5 | Apr 2 | Mar 30 | Mar 26 | Mar 22 | Mar 16 |
| 32°F | Apr 5 | Apr 1 | Mar 29 | Mar 24 | Mar 20 | Mar 16 | Mar 13 | Mar 8 | Mar 3 |
| 28°F | Mar 25 | Mar 20 | Mar 16 | Mar 13 | Mar 9 | Mar 5 | Mar 2 | Feb 27 | Feb 21 |
| 24°F | Mar 17 | Mar 10 | Mar 6 | Mar 2 | Feb 28 | Feb 24 | Feb 20 | Feb 15 | Feb 7 |
| 20°F | Mar 8 | Mar 2 | Feb 26 | Feb 20 | Feb 15 | Feb 9 | Feb 2 | Jan 30 | Jan 20 |
| 16°F | Feb 28 | Feb 18 | Feb 8 | Feb 2 | Jan 30 | Jan 25 | Jan 18 | Jan 10 | 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 14 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 29 | Nov 1 | Nov 4 | Nov 10 |
| 32°F | Oct 22 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 16 | Nov 23 |
| 28°F | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 16 | Nov 21 | Nov 25 | Dec 1 | Dec 6 |
| 24°F | Nov 9 | Nov 14 | Nov 20 | Nov 25 | Dec 1 | Dec 4 | Dec 8 | Dec 16 | Dec 25 |
| 20°F | Nov 17 | Nov 27 | Dec 2 | Dec 9 | Dec 16 | Dec 24 | Dec 30 | Jan 4 | Jan 13 |
| 16°F | Dec 1 | Dec 12 | Dec 22 | Dec 30 | Jan 1 | Jan 5 | Jan 11 | Jan 18 | 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 | 229 | 221 | 215 | 211 | 208 | 203 | 199 | 194 | 188 |
| 32°F | 252 | 244 | 239 | 234 | 229 | 224 | 219 | 214 | 206 |
| 28°F | 277 | 268 | 261 | 257 | 251 | 246 | 241 | 235 | 226 |
| 24°F | 306 | 296 | 288 | 282 | 277 | 271 | 265 | 259 | 248 |
| 20°F | 339 | 328 | 317 | 311 | 306 | 299 | 292 | 285 | 273 |
| 16°F | 365 | 360 | 348 | 341 | 334 | 328 | 321 | 313 | 303 |
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
- 86% 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
- 3,106
- Cooling degree days, base 65°F
- 2,023
- Growing degree days, base 40°F
- 8,291
- Growing degree days, base 45°F
- 6,743
- Growing degree days, base 50°F
- 5,338
- Growing degree days, base 55°F
- 4,085
- Growing degree days, base 60°F
- 2,976
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 738 | 0 | 36 |
| February | 573 | 1 | 53 |
| March | 383 | 13 | 178 |
| April | 151 | 64 | 375 |
| May | 30 | 201 | 636 |
| June | 0 | 395 | 844 |
| July | 0 | 504 | 969 |
| August | 0 | 485 | 950 |
| September | 10 | 284 | 724 |
| October | 151 | 69 | 392 |
| November | 403 | 8 | 137 |
| December | 667 | 1 | 45 |
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 13.5 km from Como. 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 USC00227921 (Senatobia). Public domain.