Tekonsha Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Coldwater St School. 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 May 2 and the first fall freeze around October 13, a growing season of about 163 days.
- Median at 36°F
- last May 14, first October 2
- Median at 32°F
- last May 2, first October 13
- Median at 28°F
- last April 21, first October 28
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 29 | May 25 | May 20 | May 17 | May 14 | May 10 | May 7 | May 3 | Apr 29 |
| 32°F | May 18 | May 13 | May 9 | May 5 | May 2 | Apr 30 | Apr 27 | Apr 23 | Apr 18 |
| 28°F | May 8 | May 1 | Apr 28 | Apr 24 | Apr 21 | Apr 18 | Apr 15 | Apr 11 | Apr 6 |
| 24°F | Apr 24 | Apr 20 | Apr 16 | Apr 12 | Apr 9 | Apr 6 | Apr 3 | Apr 1 | Mar 28 |
| 20°F | Apr 14 | Apr 7 | Apr 4 | Apr 2 | Mar 31 | Mar 28 | Mar 25 | Mar 21 | Mar 16 |
| 16°F | Apr 3 | Mar 31 | Mar 27 | Mar 23 | Mar 21 | Mar 18 | Mar 15 | Mar 11 | Mar 5 |
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 | Sep 19 | Sep 23 | Sep 27 | Sep 30 | Oct 2 | Oct 4 | Oct 7 | Oct 10 | Oct 15 |
| 32°F | Sep 30 | Oct 4 | Oct 6 | Oct 10 | Oct 13 | Oct 17 | Oct 19 | Oct 23 | Oct 30 |
| 28°F | Oct 12 | Oct 17 | Oct 21 | Oct 24 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 9 |
| 24°F | Oct 27 | Nov 1 | Nov 3 | Nov 5 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 23 |
| 20°F | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 22 | Nov 26 | Nov 30 | Dec 5 |
| 16°F | Nov 12 | Nov 18 | Nov 23 | Nov 26 | Nov 29 | Dec 1 | Dec 6 | Dec 10 | Dec 18 |
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 | 161 | 153 | 149 | 144 | 141 | 137 | 132 | 127 | 120 |
| 32°F | 182 | 176 | 171 | 167 | 163 | 158 | 153 | 149 | 142 |
| 28°F | 209 | 202 | 196 | 191 | 187 | 183 | 178 | 174 | 165 |
| 24°F | 232 | 226 | 221 | 216 | 213 | 209 | 205 | 200 | 194 |
| 20°F | 256 | 249 | 244 | 239 | 236 | 231 | 226 | 221 | 215 |
| 16°F | 279 | 270 | 264 | 259 | 255 | 250 | 246 | 241 | 234 |
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
- 100% 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
- 6,704
- Cooling degree days, base 65°F
- 567
- Growing degree days, base 40°F
- 4,694
- Growing degree days, base 45°F
- 3,600
- Growing degree days, base 50°F
- 2,638
- Growing degree days, base 55°F
- 1,809
- Growing degree days, base 60°F
- 1,112
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,289 | 0 | 0 |
| February | 1,095 | 0 | 1 |
| March | 921 | 1 | 17 |
| April | 543 | 3 | 75 |
| May | 246 | 37 | 278 |
| June | 49 | 127 | 528 |
| July | 12 | 195 | 648 |
| August | 24 | 145 | 586 |
| September | 146 | 54 | 365 |
| October | 457 | 6 | 119 |
| November | 794 | 0 | 19 |
| December | 1,128 | 0 | 2 |
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 14.6 km from Tekonsha. 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 USC00201675 (Coldwater St School). Public domain.