Oneida County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Rhinelander. 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 22 and the first fall freeze around September 24, a growing season of about 125 days.
- Median at 36°F
- last June 3, first September 13
- Median at 32°F
- last May 22, first September 24
- Median at 28°F
- last May 8, first October 4
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 18 | Jun 12 | Jun 8 | Jun 5 | Jun 3 | Jun 1 | May 29 | May 26 | May 21 |
| 32°F | Jun 4 | May 30 | May 27 | May 24 | May 22 | May 19 | May 15 | May 11 | May 6 |
| 28°F | May 24 | May 19 | May 15 | May 11 | May 8 | May 5 | May 2 | Apr 29 | Apr 26 |
| 24°F | May 13 | May 7 | May 3 | Apr 30 | Apr 29 | Apr 26 | Apr 23 | Apr 19 | Apr 14 |
| 20°F | Apr 30 | Apr 28 | Apr 24 | Apr 22 | Apr 19 | Apr 16 | Apr 13 | Apr 10 | Apr 5 |
| 16°F | Apr 24 | Apr 19 | Apr 16 | Apr 13 | Apr 10 | Apr 7 | Apr 4 | Apr 2 | Mar 29 |
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 | Aug 31 | Sep 4 | Sep 8 | Sep 10 | Sep 13 | Sep 16 | Sep 19 | Sep 22 | Sep 27 |
| 32°F | Sep 9 | Sep 15 | Sep 18 | Sep 21 | Sep 24 | Sep 27 | Sep 30 | Oct 3 | Oct 7 |
| 28°F | Sep 20 | Sep 26 | Sep 29 | Oct 1 | Oct 4 | Oct 6 | Oct 10 | Oct 15 | Oct 19 |
| 24°F | Oct 1 | Oct 5 | Oct 9 | Oct 13 | Oct 17 | Oct 20 | Oct 24 | Oct 28 | Nov 1 |
| 20°F | Oct 13 | Oct 19 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 7 | Nov 12 |
| 16°F | Oct 25 | Oct 31 | Nov 1 | Nov 4 | Nov 8 | Nov 11 | Nov 13 | Nov 17 | Nov 22 |
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 | 121 | 114 | 109 | 106 | 102 | 98 | 94 | 89 | 81 |
| 32°F | 144 | 137 | 133 | 129 | 125 | 121 | 117 | 112 | 105 |
| 28°F | 166 | 159 | 153 | 149 | 146 | 142 | 137 | 132 | 124 |
| 24°F | 191 | 183 | 178 | 173 | 169 | 165 | 159 | 154 | 147 |
| 20°F | 214 | 206 | 201 | 196 | 192 | 188 | 184 | 178 | 170 |
| 16°F | 230 | 223 | 219 | 215 | 212 | 207 | 204 | 199 | 192 |
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
- 9,301
- Cooling degree days, base 65°F
- 240
- Growing degree days, base 40°F
- 3,435
- Growing degree days, base 45°F
- 2,541
- Growing degree days, base 50°F
- 1,761
- Growing degree days, base 55°F
- 1,103
- Growing degree days, base 60°F
- 588
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,682 | 0 | 0 |
| February | 1,429 | 0 | 0 |
| March | 1,228 | 0 | 4 |
| April | 789 | 0 | 21 |
| May | 396 | 11 | 156 |
| June | 135 | 48 | 367 |
| July | 56 | 95 | 504 |
| August | 88 | 65 | 442 |
| September | 279 | 20 | 225 |
| October | 672 | 1 | 41 |
| November | 1,068 | 0 | 3 |
| December | 1,479 | 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 13.2 km from Oneida County. 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 USC00477113 (Rhinelander). Public domain.