Tipton Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Tipton 5 Sw. 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 April 23 and the first fall freeze around October 17, a growing season of about 174 days.
- Median at 36°F
- last May 5, first October 6
- Median at 32°F
- last April 23, first October 17
- Median at 28°F
- last April 11, first October 28
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 | May 20 | May 14 | May 10 | May 7 | May 5 | May 2 | Apr 29 | Apr 26 | Apr 20 |
| 32°F | May 9 | May 4 | Apr 30 | Apr 27 | Apr 23 | Apr 20 | Apr 18 | Apr 14 | Apr 9 |
| 28°F | Apr 29 | Apr 22 | Apr 18 | Apr 15 | Apr 11 | Apr 8 | Apr 5 | Apr 2 | Mar 28 |
| 24°F | Apr 15 | Apr 9 | Apr 5 | Apr 2 | Mar 31 | Mar 29 | Mar 25 | Mar 21 | Mar 14 |
| 20°F | Apr 4 | Mar 31 | Mar 27 | Mar 24 | Mar 21 | Mar 17 | Mar 13 | Mar 9 | Mar 3 |
| 16°F | Mar 29 | Mar 22 | Mar 17 | Mar 14 | Mar 11 | Mar 8 | Mar 4 | Feb 28 | Feb 19 |
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 24 | Sep 28 | Oct 1 | Oct 4 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 20 |
| 32°F | Oct 3 | Oct 8 | Oct 12 | Oct 15 | Oct 17 | Oct 20 | Oct 22 | Oct 26 | Nov 1 |
| 28°F | Oct 15 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 1 | Nov 4 | Nov 10 |
| 24°F | Oct 26 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 20 | Nov 25 |
| 20°F | Nov 5 | Nov 9 | Nov 13 | Nov 17 | Nov 20 | Nov 24 | Nov 29 | Dec 2 | Dec 9 |
| 16°F | Nov 12 | Nov 19 | Nov 24 | Nov 28 | Dec 1 | Dec 4 | Dec 8 | Dec 14 | Dec 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 | 171 | 165 | 160 | 157 | 153 | 149 | 145 | 141 | 134 |
| 32°F | 194 | 188 | 182 | 178 | 174 | 170 | 165 | 161 | 154 |
| 28°F | 218 | 211 | 207 | 202 | 198 | 194 | 190 | 184 | 178 |
| 24°F | 247 | 237 | 232 | 227 | 223 | 218 | 214 | 209 | 204 |
| 20°F | 270 | 261 | 256 | 251 | 246 | 242 | 237 | 232 | 223 |
| 16°F | 291 | 282 | 275 | 270 | 265 | 260 | 254 | 249 | 242 |
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
- 5,879
- Cooling degree days, base 65°F
- 875
- Growing degree days, base 40°F
- 5,488
- Growing degree days, base 45°F
- 4,298
- Growing degree days, base 50°F
- 3,247
- Growing degree days, base 55°F
- 2,323
- Growing degree days, base 60°F
- 1,530
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,215 | 0 | 2 |
| February | 998 | 0 | 3 |
| March | 804 | 2 | 34 |
| April | 440 | 8 | 127 |
| May | 172 | 70 | 374 |
| June | 25 | 200 | 626 |
| July | 5 | 262 | 722 |
| August | 9 | 213 | 670 |
| September | 88 | 103 | 468 |
| October | 367 | 17 | 182 |
| November | 710 | 1 | 35 |
| December | 1,046 | 0 | 5 |
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 8.7 km from Tipton. 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 USC00128784 (Tipton 5 Sw). Public domain.