Bailey Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Bailey. 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 June 16 and the first fall freeze around September 8, a growing season of about 84 days.
- Median at 32°F
- last June 16, first September 8
- Median at 28°F
- last May 30, first September 19
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 | – | – | – | – | – | – | – | – | – |
| 32°F | Jul 1 | Jun 27 | Jun 22 | Jun 20 | Jun 16 | Jun 13 | Jun 11 | Jun 7 | Jun 2 |
| 28°F | Jun 15 | Jun 9 | Jun 5 | Jun 2 | May 30 | May 26 | May 23 | May 19 | May 14 |
| 24°F | May 26 | May 20 | May 16 | May 13 | May 11 | May 9 | May 6 | May 4 | Apr 30 |
| 20°F | May 13 | May 8 | May 5 | May 3 | May 1 | Apr 29 | Apr 26 | Apr 22 | Apr 17 |
| 16°F | May 6 | May 1 | Apr 28 | Apr 24 | Apr 21 | Apr 18 | Apr 14 | Apr 9 | Apr 5 |
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 | – | – | – | – | – | – | – | – | – |
| 32°F | Aug 27 | Sep 1 | Sep 3 | Sep 6 | Sep 8 | Sep 11 | Sep 14 | Sep 16 | Sep 20 |
| 28°F | Sep 6 | Sep 11 | Sep 14 | Sep 17 | Sep 19 | Sep 22 | Sep 25 | Sep 27 | Oct 1 |
| 24°F | Sep 16 | Sep 21 | Sep 25 | Sep 28 | Sep 30 | Oct 3 | Oct 5 | Oct 9 | Oct 13 |
| 20°F | Sep 26 | Oct 1 | Oct 5 | Oct 8 | Oct 11 | Oct 13 | Oct 16 | Oct 20 | Oct 25 |
| 16°F | Oct 6 | Oct 10 | Oct 13 | Oct 17 | Oct 19 | Oct 22 | Oct 25 | Oct 29 | Nov 2 |
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 | 76 | 69 | 65 | 60 | 56 | 52 | 47 | 42 | 35 |
| 32°F | 104 | 97 | 92 | 87 | 84 | 79 | 75 | 70 | 64 |
| 28°F | 129 | 123 | 118 | 114 | 111 | 106 | 102 | 97 | 90 |
| 24°F | 158 | 151 | 146 | 143 | 139 | 135 | 132 | 127 | 120 |
| 20°F | 181 | 174 | 169 | 165 | 161 | 158 | 153 | 149 | 141 |
| 16°F | 201 | 194 | 189 | 184 | 180 | 176 | 171 | 166 | 160 |
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
- 8,719
- Cooling degree days, base 65°F
- 19
- Growing degree days, base 40°F
- 2,673
- Growing degree days, base 45°F
- 1,794
- Growing degree days, base 50°F
- 1,085
- Growing degree days, base 55°F
- 535
- Growing degree days, base 60°F
- 170
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,296 | 0 | 0 |
| February | 1,120 | 0 | 0 |
| March | 995 | 0 | 0 |
| April | 795 | 0 | 3 |
| May | 558 | 0 | 49 |
| June | 255 | 3 | 212 |
| July | 107 | 11 | 369 |
| August | 163 | 5 | 309 |
| September | 365 | 0 | 132 |
| October | 727 | 0 | 11 |
| November | 1,035 | 0 | 0 |
| December | 1,304 | 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 0.3 km from Bailey. 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 USC00050454 (Bailey). Public domain.