Allendale Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Grand Haven Wwtp. 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 April 30 and the first fall freeze around October 24, a growing season of about 175 days.
- Median at 36°F
- last May 13, first October 9
- Median at 32°F
- last April 30, first October 24
- Median at 28°F
- last April 18, first November 5
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 30 | May 24 | May 20 | May 17 | May 13 | May 9 | May 5 | May 2 | Apr 26 |
| 32°F | May 16 | May 12 | May 6 | May 3 | Apr 30 | Apr 28 | Apr 24 | Apr 20 | Apr 17 |
| 28°F | May 6 | Apr 30 | Apr 25 | Apr 21 | Apr 18 | Apr 16 | Apr 12 | Apr 8 | Apr 4 |
| 24°F | Apr 21 | Apr 17 | Apr 13 | Apr 9 | Apr 6 | Apr 3 | Apr 1 | Mar 30 | Mar 22 |
| 20°F | Apr 10 | Apr 5 | Apr 2 | Mar 30 | Mar 28 | Mar 24 | Mar 20 | Mar 16 | Mar 10 |
| 16°F | Mar 31 | Mar 28 | Mar 24 | Mar 20 | Mar 16 | Mar 13 | Mar 10 | Mar 6 | Feb 28 |
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 25 | Sep 30 | Oct 3 | Oct 6 | Oct 9 | Oct 12 | Oct 16 | Oct 19 | Oct 25 |
| 32°F | Oct 5 | Oct 11 | Oct 16 | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 6 |
| 28°F | Oct 21 | Oct 27 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 16 | Nov 22 |
| 24°F | Nov 2 | Nov 6 | Nov 11 | Nov 16 | Nov 20 | Nov 24 | Nov 28 | Dec 1 | Dec 8 |
| 20°F | Nov 15 | Nov 22 | Nov 26 | Dec 1 | Dec 3 | Dec 7 | Dec 11 | Dec 17 | Dec 24 |
| 16°F | Nov 29 | Dec 4 | Dec 8 | Dec 12 | Dec 17 | Dec 21 | Dec 24 | Dec 29 | Jan 6 |
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 | 172 | 164 | 158 | 154 | 150 | 145 | 141 | 135 | 127 |
| 32°F | 194 | 189 | 184 | 179 | 175 | 170 | 165 | 160 | 151 |
| 28°F | 221 | 214 | 209 | 204 | 200 | 195 | 191 | 186 | 179 |
| 24°F | 251 | 241 | 235 | 230 | 225 | 221 | 216 | 211 | 205 |
| 20°F | 276 | 269 | 262 | 256 | 251 | 246 | 241 | 235 | 227 |
| 16°F | 297 | 290 | 285 | 280 | 275 | 270 | 265 | 259 | 250 |
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
- 6,586
- Cooling degree days, base 65°F
- 534
- Growing degree days, base 40°F
- 4,593
- Growing degree days, base 45°F
- 3,505
- Growing degree days, base 50°F
- 2,562
- Growing degree days, base 55°F
- 1,748
- Growing degree days, base 60°F
- 1,064
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,224 | 0 | 0 |
| February | 1,082 | 0 | 0 |
| March | 964 | 2 | 15 |
| April | 593 | 0 | 44 |
| May | 272 | 23 | 243 |
| June | 49 | 98 | 500 |
| July | 14 | 199 | 649 |
| August | 20 | 155 | 600 |
| September | 122 | 53 | 383 |
| October | 430 | 4 | 114 |
| November | 757 | 0 | 15 |
| December | 1,059 | 0 | 1 |
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 22.6 km from Allendale. 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 USC00203295 (Grand Haven Wwtp). Public domain.