Myton Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Myton. 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 7 and the first fall freeze around October 5, a growing season of about 149 days.
- Median at 36°F
- last May 23, first September 26
- Median at 32°F
- last May 7, first October 5
- Median at 28°F
- last April 24, first October 18
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 8 | Jun 2 | May 30 | May 26 | May 23 | May 19 | May 16 | May 11 | May 7 |
| 32°F | May 25 | May 19 | May 14 | May 10 | May 7 | May 4 | May 1 | Apr 28 | Apr 23 |
| 28°F | May 9 | May 4 | Apr 30 | Apr 27 | Apr 24 | Apr 21 | Apr 17 | Apr 13 | Apr 7 |
| 24°F | Apr 26 | Apr 21 | Apr 16 | Apr 12 | Apr 9 | Apr 6 | Apr 2 | Mar 31 | Mar 23 |
| 20°F | Apr 12 | Apr 6 | Apr 2 | Mar 31 | Mar 27 | Mar 22 | Mar 18 | Mar 13 | Mar 7 |
| 16°F | Mar 31 | Mar 23 | Mar 16 | Mar 11 | Mar 9 | Mar 6 | Mar 3 | Feb 28 | Feb 23 |
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 14 | Sep 18 | Sep 21 | Sep 24 | Sep 26 | Sep 28 | Oct 1 | Oct 4 | Oct 9 |
| 32°F | Sep 22 | Sep 26 | Sep 29 | Oct 3 | Oct 5 | Oct 9 | Oct 13 | Oct 16 | Oct 21 |
| 28°F | Oct 1 | Oct 7 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 23 | Oct 26 | Oct 31 |
| 24°F | Oct 13 | Oct 18 | Oct 22 | Oct 25 | Oct 27 | Oct 30 | Nov 2 | Nov 5 | Nov 9 |
| 20°F | Oct 23 | Oct 28 | Oct 31 | Nov 3 | Nov 6 | Nov 8 | Nov 11 | Nov 14 | Nov 19 |
| 16°F | Oct 31 | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 17 | Nov 20 | Nov 23 | Nov 27 |
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 | 146 | 139 | 135 | 130 | 125 | 121 | 116 | 110 | 104 |
| 32°F | 171 | 164 | 158 | 153 | 149 | 145 | 140 | 134 | 124 |
| 28°F | 196 | 188 | 183 | 179 | 174 | 170 | 165 | 159 | 151 |
| 24°F | 220 | 213 | 207 | 203 | 198 | 194 | 190 | 184 | 176 |
| 20°F | 247 | 237 | 231 | 225 | 221 | 217 | 212 | 206 | 197 |
| 16°F | 268 | 261 | 256 | 251 | 247 | 242 | 236 | 230 | 221 |
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
- 6,837
- Cooling degree days, base 65°F
- 685
- Growing degree days, base 40°F
- 4,845
- Growing degree days, base 45°F
- 3,736
- Growing degree days, base 50°F
- 2,767
- Growing degree days, base 55°F
- 1,939
- Growing degree days, base 60°F
- 1,245
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,430 | 0 | 0 |
| February | 1,064 | 0 | 0 |
| March | 764 | 0 | 10 |
| April | 485 | 0 | 72 |
| May | 236 | 14 | 263 |
| June | 51 | 124 | 524 |
| July | 3 | 284 | 745 |
| August | 7 | 218 | 676 |
| September | 114 | 45 | 386 |
| October | 476 | 1 | 89 |
| November | 888 | 0 | 2 |
| December | 1,319 | 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 0.1 km from Myton. 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 USC00425969 (Myton). Public domain.