Elgin Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Elgin 1 N. 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 4 and the first fall freeze around November 24, a growing season of about 264 days.
- Median at 36°F
- last March 18, first November 12
- Median at 32°F
- last March 4, first November 24
- Median at 28°F
- last February 21, first December 9
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 6 | Apr 1 | Mar 26 | Mar 22 | Mar 18 | Mar 14 | Mar 10 | Mar 5 | Feb 28 |
| 32°F | Mar 23 | Mar 17 | Mar 12 | Mar 8 | Mar 4 | Mar 1 | Feb 26 | Feb 20 | Feb 12 |
| 28°F | Mar 13 | Mar 7 | Mar 2 | Feb 26 | Feb 21 | Feb 14 | Feb 6 | Jan 29 | Jan 18 |
| 24°F | Mar 4 | Feb 25 | Feb 15 | Feb 9 | Feb 2 | Jan 27 | Jan 19 | Jan 11 | Dec 31 |
| 20°F | Feb 23 | Feb 11 | Feb 6 | Jan 31 | Jan 23 | Jan 16 | Jan 8 | Dec 31 | Dec 21 |
| 16°F | Feb 16 | Feb 8 | Feb 6 | Feb 1 | Jan 28 | Jan 21 | Jan 10 | Jan 6 | Dec 29 |
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 31 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 19 | Nov 23 | Nov 30 |
| 32°F | Nov 5 | Nov 11 | Nov 15 | Nov 20 | Nov 24 | Nov 28 | Dec 2 | Dec 6 | Dec 13 |
| 28°F | Nov 17 | Nov 25 | Nov 30 | Dec 4 | Dec 9 | Dec 15 | Dec 20 | Dec 27 | Jan 5 |
| 24°F | Dec 1 | Dec 7 | Dec 17 | Dec 25 | Dec 31 | Jan 5 | Jan 9 | Jan 18 | Feb 1 |
| 20°F | Dec 10 | Dec 23 | Dec 30 | Jan 4 | Jan 7 | Jan 13 | Jan 21 | Feb 1 | Feb 8 |
| 16°F | Dec 23 | Jan 2 | Jan 6 | Jan 12 | Jan 21 | Jan 30 | Feb 3 | Feb 6 | Feb 14 |
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 | 266 | 257 | 251 | 245 | 240 | 235 | 230 | 223 | 215 |
| 32°F | 298 | 284 | 277 | 270 | 264 | 258 | 252 | 246 | 238 |
| 28°F | 333 | 318 | 310 | 302 | 295 | 287 | 279 | 270 | 260 |
| 24°F | 365 | 353 | 344 | 334 | 325 | 317 | 309 | 302 | 286 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 354 | 342 | 332 | 319 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 349 |
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
- 89% of years
- 20°F or colder
- 52% of years
- 16°F or colder
- 16% 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
- 1,751
- Cooling degree days, base 65°F
- 2,891
- Growing degree days, base 40°F
- 10,324
- Growing degree days, base 45°F
- 8,596
- Growing degree days, base 50°F
- 6,959
- Growing degree days, base 55°F
- 5,449
- Growing degree days, base 60°F
- 4,088
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 472 | 7 | 120 |
| February | 336 | 14 | 169 |
| March | 191 | 47 | 344 |
| April | 56 | 134 | 530 |
| May | 6 | 316 | 775 |
| June | 0 | 495 | 945 |
| July | 0 | 594 | 1,059 |
| August | 0 | 608 | 1,072 |
| September | 2 | 420 | 868 |
| October | 46 | 196 | 617 |
| November | 217 | 49 | 313 |
| December | 425 | 11 | 147 |
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 1.6 km from Elgin. 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 USC00412820 (Elgin 1 N). Public domain.