Rapids Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Lockport 4E. 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 26 and the first fall freeze around October 26, a growing season of about 182 days.
- Median at 36°F
- last May 5, first October 12
- Median at 32°F
- last April 26, first October 26
- Median at 28°F
- last April 13, first November 8
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 19 | May 14 | May 11 | May 7 | May 5 | May 2 | Apr 30 | Apr 27 | Apr 23 |
| 32°F | May 8 | May 3 | Apr 30 | Apr 28 | Apr 26 | Apr 23 | Apr 20 | Apr 17 | Apr 13 |
| 28°F | Apr 27 | Apr 22 | Apr 19 | Apr 16 | Apr 13 | Apr 10 | Apr 7 | Apr 5 | Apr 2 |
| 24°F | Apr 16 | Apr 11 | Apr 7 | Apr 5 | Apr 3 | Apr 2 | Mar 31 | Mar 27 | Mar 22 |
| 20°F | Apr 5 | Apr 2 | Mar 31 | Mar 28 | Mar 25 | Mar 22 | Mar 20 | Mar 16 | Mar 12 |
| 16°F | Mar 30 | Mar 26 | Mar 22 | Mar 20 | Mar 17 | Mar 14 | Mar 11 | Mar 7 | Mar 1 |
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 1 | Oct 3 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 22 | Oct 29 |
| 32°F | Oct 9 | Oct 14 | Oct 18 | Oct 22 | Oct 26 | Oct 29 | Nov 1 | Nov 4 | Nov 10 |
| 28°F | Oct 24 | Oct 30 | Nov 2 | Nov 4 | Nov 8 | Nov 11 | Nov 15 | Nov 19 | Nov 24 |
| 24°F | Nov 5 | Nov 10 | Nov 14 | Nov 17 | Nov 21 | Nov 24 | Nov 27 | Dec 1 | Dec 5 |
| 20°F | Nov 14 | Nov 20 | Nov 24 | Nov 28 | Dec 1 | Dec 3 | Dec 5 | Dec 10 | Dec 16 |
| 16°F | Nov 22 | Nov 28 | Dec 2 | Dec 5 | Dec 8 | Dec 12 | Dec 16 | Dec 19 | Dec 26 |
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 | 179 | 172 | 168 | 164 | 160 | 156 | 152 | 147 | 142 |
| 32°F | 202 | 196 | 190 | 186 | 182 | 179 | 174 | 169 | 162 |
| 28°F | 229 | 221 | 216 | 212 | 208 | 204 | 200 | 195 | 187 |
| 24°F | 251 | 244 | 240 | 235 | 232 | 228 | 223 | 218 | 211 |
| 20°F | 271 | 263 | 257 | 253 | 249 | 246 | 241 | 235 | 228 |
| 16°F | 290 | 282 | 276 | 272 | 268 | 263 | 259 | 253 | 245 |
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
- 6,389
- Cooling degree days, base 65°F
- 633
- Growing degree days, base 40°F
- 4,843
- Growing degree days, base 45°F
- 3,734
- Growing degree days, base 50°F
- 2,757
- Growing degree days, base 55°F
- 1,918
- Growing degree days, base 60°F
- 1,206
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,228 | 0 | 1 |
| February | 1,061 | 0 | 0 |
| March | 935 | 0 | 11 |
| April | 577 | 1 | 55 |
| May | 235 | 34 | 283 |
| June | 44 | 123 | 530 |
| July | 6 | 216 | 676 |
| August | 14 | 181 | 632 |
| September | 109 | 71 | 414 |
| October | 417 | 7 | 130 |
| November | 713 | 0 | 24 |
| December | 1,052 | 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 10.3 km from Rapids. 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 USC00304844 (Lockport 4E). Public domain.