Tyrone Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Philipsburg 2 S. 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 13 and the first fall freeze around October 1, a growing season of about 142 days.
- Median at 36°F
- last May 27, first September 22
- Median at 32°F
- last May 13, first October 1
- Median at 28°F
- last April 30, first October 16
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 13 | Jun 6 | Jun 2 | May 31 | May 27 | May 24 | May 20 | May 16 | May 8 |
| 32°F | May 29 | May 24 | May 21 | May 17 | May 13 | May 8 | May 4 | Apr 30 | Apr 25 |
| 28°F | May 20 | May 13 | May 8 | May 4 | Apr 30 | Apr 27 | Apr 23 | Apr 19 | Apr 16 |
| 24°F | May 8 | May 1 | Apr 26 | Apr 22 | Apr 19 | Apr 16 | Apr 13 | Apr 8 | Apr 4 |
| 20°F | Apr 21 | Apr 15 | Apr 12 | Apr 8 | Apr 5 | Apr 2 | Mar 31 | Mar 27 | Mar 21 |
| 16°F | Apr 7 | Apr 3 | Mar 31 | Mar 29 | Mar 27 | Mar 24 | Mar 20 | Mar 16 | Mar 12 |
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 6 | Sep 12 | Sep 16 | Sep 19 | Sep 22 | Sep 24 | Sep 27 | Sep 30 | Oct 5 |
| 32°F | Sep 19 | Sep 23 | Sep 26 | Sep 29 | Oct 1 | Oct 4 | Oct 8 | Oct 12 | Oct 18 |
| 28°F | Oct 1 | Oct 4 | Oct 8 | Oct 12 | Oct 16 | Oct 20 | Oct 23 | Oct 28 | Nov 3 |
| 24°F | Oct 10 | Oct 17 | Oct 22 | Oct 26 | Oct 30 | Nov 1 | Nov 4 | Nov 8 | Nov 13 |
| 20°F | Oct 28 | Nov 2 | Nov 5 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 22 | Nov 28 |
| 16°F | Nov 8 | Nov 13 | Nov 17 | Nov 20 | Nov 24 | Nov 28 | Dec 1 | Dec 5 | Dec 13 |
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 | 141 | 134 | 128 | 123 | 118 | 114 | 109 | 103 | 95 |
| 32°F | 167 | 159 | 153 | 148 | 142 | 138 | 134 | 128 | 120 |
| 28°F | 192 | 184 | 179 | 173 | 169 | 164 | 158 | 152 | 144 |
| 24°F | 218 | 210 | 205 | 199 | 194 | 189 | 184 | 178 | 170 |
| 20°F | 242 | 235 | 229 | 225 | 221 | 216 | 211 | 206 | 198 |
| 16°F | 269 | 259 | 253 | 248 | 243 | 238 | 234 | 229 | 222 |
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
- 7,031
- Cooling degree days, base 65°F
- 357
- Growing degree days, base 40°F
- 4,231
- Growing degree days, base 45°F
- 3,163
- Growing degree days, base 50°F
- 2,232
- Growing degree days, base 55°F
- 1,442
- Growing degree days, base 60°F
- 811
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,277 | 0 | 1 |
| February | 1,099 | 0 | 1 |
| March | 980 | 0 | 11 |
| April | 581 | 3 | 67 |
| May | 294 | 20 | 229 |
| June | 96 | 70 | 427 |
| July | 30 | 132 | 567 |
| August | 46 | 96 | 515 |
| September | 185 | 32 | 306 |
| October | 512 | 3 | 90 |
| November | 809 | 0 | 14 |
| December | 1,124 | 0 | 4 |
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 22.5 km from Tyrone. 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 USC00366921 (Philipsburg 2 S). Public domain.