Steep Falls Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for East Hiram. 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 12 and the first fall freeze around October 1, a growing season of about 140 days.
- Median at 36°F
- last May 25, first September 21
- Median at 32°F
- last May 12, first October 1
- Median at 28°F
- last April 29, first October 11
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 | Jun 6 | Jun 2 | May 30 | May 27 | May 25 | May 22 | May 19 | May 16 | May 12 |
| 32°F | May 25 | May 20 | May 17 | May 14 | May 12 | May 10 | May 7 | May 4 | May 1 |
| 28°F | May 10 | May 5 | May 2 | Apr 30 | Apr 29 | Apr 27 | Apr 24 | Apr 22 | Apr 16 |
| 24°F | Apr 25 | Apr 22 | Apr 19 | Apr 17 | Apr 14 | Apr 11 | Apr 9 | Apr 7 | Apr 4 |
| 20°F | Apr 17 | Apr 13 | Apr 10 | Apr 7 | Apr 5 | Apr 4 | Apr 2 | Mar 31 | Mar 24 |
| 16°F | Apr 8 | Apr 4 | Apr 2 | Apr 1 | Mar 30 | Mar 27 | Mar 23 | Mar 19 | Mar 15 |
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 8 | Sep 13 | Sep 16 | Sep 18 | Sep 21 | Sep 24 | Sep 27 | Oct 1 | Oct 3 |
| 32°F | Sep 19 | Sep 23 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 7 | Oct 12 |
| 28°F | Sep 30 | Oct 2 | Oct 5 | Oct 8 | Oct 11 | Oct 15 | Oct 18 | Oct 23 | Oct 31 |
| 24°F | Oct 10 | Oct 15 | Oct 19 | Oct 21 | Oct 25 | Oct 28 | Nov 1 | Nov 5 | Nov 10 |
| 20°F | Oct 25 | Oct 31 | Nov 2 | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 23 |
| 16°F | Nov 6 | Nov 11 | Nov 15 | Nov 18 | Nov 20 | Nov 23 | Nov 26 | Nov 29 | Dec 4 |
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 | 134 | 130 | 126 | 121 | 119 | 115 | 111 | 106 | 101 |
| 32°F | 158 | 152 | 148 | 144 | 140 | 137 | 133 | 129 | 123 |
| 28°F | 186 | 179 | 172 | 169 | 165 | 161 | 157 | 153 | 146 |
| 24°F | 212 | 206 | 201 | 197 | 193 | 189 | 185 | 180 | 174 |
| 20°F | 234 | 228 | 224 | 219 | 215 | 212 | 208 | 203 | 196 |
| 16°F | 254 | 247 | 243 | 239 | 235 | 232 | 228 | 224 | 218 |
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
- 8,086
- Cooling degree days, base 65°F
- 265
- Growing degree days, base 40°F
- 3,692
- Growing degree days, base 45°F
- 2,728
- Growing degree days, base 50°F
- 1,897
- Growing degree days, base 55°F
- 1,199
- Growing degree days, base 60°F
- 644
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,472 | 0 | 1 |
| February | 1,271 | 0 | 0 |
| March | 1,118 | 0 | 1 |
| April | 697 | 1 | 26 |
| May | 363 | 8 | 154 |
| June | 128 | 48 | 373 |
| July | 33 | 108 | 539 |
| August | 53 | 79 | 491 |
| September | 228 | 21 | 259 |
| October | 585 | 1 | 48 |
| November | 885 | 0 | 5 |
| December | 1,254 | 0 | 0 |
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 12.4 km from Steep Falls. 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 USC00172238 (East Hiram). Public domain.