Basin City Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Eltopia 8 Wsw. 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 21 and the first fall freeze around October 22, a growing season of about 182 days.
- Median at 36°F
- last May 5, first October 9
- Median at 32°F
- last April 21, first October 22
- Median at 28°F
- last March 30, first November 1
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 21 | May 15 | May 11 | May 8 | May 5 | May 2 | Apr 30 | Apr 28 | Apr 23 |
| 32°F | May 6 | May 1 | Apr 29 | Apr 25 | Apr 21 | Apr 18 | Apr 14 | Apr 9 | Apr 3 |
| 28°F | Apr 18 | Apr 10 | Apr 5 | Apr 2 | Mar 30 | Mar 26 | Mar 22 | Mar 16 | Mar 8 |
| 24°F | Mar 29 | Mar 21 | Mar 15 | Mar 10 | Mar 6 | Mar 3 | Feb 28 | Feb 24 | Feb 17 |
| 20°F | Mar 12 | Mar 5 | Feb 28 | Feb 24 | Feb 18 | Feb 13 | Feb 6 | Jan 31 | Jan 15 |
| 16°F | Feb 28 | Feb 22 | Feb 15 | Feb 6 | Jan 31 | Jan 23 | Jan 14 | Jan 6 | Dec 25 |
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 27 | Oct 1 | Oct 4 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 17 | Oct 23 |
| 32°F | Oct 7 | Oct 12 | Oct 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 30 | Nov 4 |
| 28°F | Oct 18 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 18 |
| 24°F | Oct 28 | Nov 2 | Nov 5 | Nov 10 | Nov 13 | Nov 18 | Nov 22 | Nov 26 | Dec 1 |
| 20°F | Nov 5 | Nov 13 | Nov 19 | Nov 24 | Nov 28 | Dec 2 | Dec 7 | Dec 14 | Dec 23 |
| 16°F | Nov 15 | Nov 25 | Dec 1 | Dec 6 | Dec 11 | Dec 17 | Dec 24 | Jan 1 | Jan 14 |
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 | 173 | 167 | 162 | 158 | 155 | 151 | 146 | 141 | 135 |
| 32°F | 204 | 197 | 191 | 186 | 182 | 178 | 174 | 169 | 162 |
| 28°F | 242 | 233 | 226 | 221 | 215 | 210 | 205 | 200 | 192 |
| 24°F | 281 | 270 | 262 | 256 | 250 | 244 | 239 | 232 | 223 |
| 20°F | 321 | 307 | 299 | 290 | 283 | 276 | 269 | 261 | 250 |
| 16°F | 354 | 341 | 333 | 325 | 316 | 308 | 300 | 290 | 275 |
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
- 96% 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
- 5,309
- Cooling degree days, base 65°F
- 543
- Growing degree days, base 40°F
- 5,055
- Growing degree days, base 45°F
- 3,767
- Growing degree days, base 50°F
- 2,688
- Growing degree days, base 55°F
- 1,793
- Growing degree days, base 60°F
- 1,073
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 984 | 0 | 0 |
| February | 756 | 0 | 2 |
| March | 617 | 0 | 21 |
| April | 407 | 1 | 89 |
| May | 196 | 25 | 299 |
| June | 67 | 65 | 449 |
| July | 10 | 209 | 663 |
| August | 13 | 197 | 649 |
| September | 104 | 45 | 392 |
| October | 415 | 1 | 113 |
| November | 748 | 0 | 9 |
| December | 992 | 0 | 1 |
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 21.7 km from Basin City. 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 USC00452542 (Eltopia 8 Wsw). Public domain.