Paonia Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Paonia 1SW. 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 3 and the first fall freeze around October 12, a growing season of about 159 days.
- Median at 36°F
- last May 17, first October 1
- Median at 32°F
- last May 3, first October 12
- Median at 28°F
- last April 23, first October 21
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 1 | May 28 | May 23 | May 20 | May 17 | May 14 | May 10 | May 6 | May 3 |
| 32°F | May 18 | May 14 | May 9 | May 5 | May 3 | May 1 | Apr 29 | Apr 26 | Apr 22 |
| 28°F | May 6 | May 2 | Apr 29 | Apr 26 | Apr 23 | Apr 20 | Apr 17 | Apr 13 | Apr 8 |
| 24°F | Apr 27 | Apr 21 | Apr 16 | Apr 12 | Apr 9 | Apr 5 | Apr 1 | Mar 27 | Mar 17 |
| 20°F | Apr 14 | Apr 7 | Apr 2 | Mar 29 | Mar 22 | Mar 17 | Mar 11 | Mar 6 | Mar 1 |
| 16°F | Mar 27 | Mar 17 | Mar 10 | Mar 7 | Mar 3 | Feb 28 | Feb 23 | Feb 17 | Feb 11 |
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 21 | Sep 24 | Sep 27 | Sep 29 | Oct 1 | Oct 4 | Oct 7 | Oct 12 | Oct 16 |
| 32°F | Sep 27 | Oct 1 | Oct 5 | Oct 8 | Oct 12 | Oct 15 | Oct 18 | Oct 21 | Oct 25 |
| 28°F | Oct 6 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 5 |
| 24°F | Oct 16 | Oct 20 | Oct 24 | Oct 27 | Oct 31 | Nov 3 | Nov 6 | Nov 10 | Nov 16 |
| 20°F | Oct 25 | Oct 31 | Nov 3 | Nov 7 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 25 |
| 16°F | Nov 2 | Nov 9 | Nov 13 | Nov 17 | Nov 20 | Nov 23 | Nov 27 | Nov 30 | Dec 5 |
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 | 158 | 151 | 146 | 141 | 137 | 133 | 129 | 123 | 116 |
| 32°F | 179 | 172 | 168 | 163 | 159 | 155 | 151 | 146 | 139 |
| 28°F | 202 | 194 | 189 | 184 | 180 | 176 | 171 | 166 | 159 |
| 24°F | 228 | 218 | 212 | 207 | 202 | 197 | 192 | 187 | 179 |
| 20°F | 257 | 249 | 242 | 235 | 230 | 224 | 219 | 212 | 204 |
| 16°F | 287 | 277 | 271 | 266 | 261 | 255 | 249 | 240 | 229 |
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
- 5,912
- Cooling degree days, base 65°F
- 683
- Growing degree days, base 40°F
- 5,070
- Growing degree days, base 45°F
- 3,892
- Growing degree days, base 50°F
- 2,863
- Growing degree days, base 55°F
- 1,991
- Growing degree days, base 60°F
- 1,264
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,164 | 0 | 0 |
| February | 883 | 0 | 0 |
| March | 704 | 0 | 17 |
| April | 488 | 0 | 77 |
| May | 240 | 14 | 261 |
| June | 44 | 123 | 530 |
| July | 2 | 275 | 738 |
| August | 5 | 216 | 676 |
| September | 91 | 55 | 419 |
| October | 404 | 1 | 132 |
| November | 755 | 0 | 13 |
| December | 1,133 | 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 3.2 km from Paonia. 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 USC00056306 (Paonia 1SW). Public domain.