Sandy Valley Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Goodsprings. 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 March 17 and the first fall freeze around November 20, a growing season of about 245 days.
- Median at 36°F
- last April 7, first November 9
- Median at 32°F
- last March 17, first November 20
- Median at 28°F
- last February 26, first December 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 | Apr 25 | Apr 19 | Apr 15 | Apr 11 | Apr 7 | Apr 4 | Mar 31 | Mar 24 | Mar 15 |
| 32°F | Apr 11 | Apr 4 | Mar 31 | Mar 24 | Mar 17 | Mar 12 | Mar 7 | Mar 1 | Feb 23 |
| 28°F | Mar 27 | Mar 14 | Mar 7 | Mar 2 | Feb 26 | Feb 21 | Feb 15 | Feb 7 | Jan 30 |
| 24°F | Mar 5 | Feb 24 | Feb 14 | Feb 6 | Jan 31 | Jan 24 | Jan 13 | Jan 6 | Dec 28 |
| 20°F | Feb 26 | Feb 10 | Jan 31 | Jan 16 | Jan 9 | Jan 3 | Dec 31 | Dec 24 | Dec 15 |
| 16°F | Feb 27 | Jan 31 | Jan 16 | Jan 9 | Jan 5 | Jan 1 | Dec 30 | Dec 21 | Dec 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 | Oct 24 | Oct 30 | Nov 3 | Nov 6 | Nov 9 | Nov 13 | Nov 15 | Nov 19 | Nov 22 |
| 32°F | Nov 4 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 22 | Nov 26 | Nov 30 | Dec 5 |
| 28°F | Nov 16 | Nov 21 | Nov 25 | Nov 28 | Dec 1 | Dec 4 | Dec 9 | Dec 13 | Dec 21 |
| 24°F | Nov 26 | Dec 1 | Dec 6 | Dec 11 | Dec 15 | Dec 21 | Dec 26 | Jan 2 | Jan 15 |
| 20°F | Dec 3 | Dec 11 | Dec 17 | Dec 23 | Dec 28 | Jan 1 | Jan 7 | Jan 20 | Feb 9 |
| 16°F | Dec 8 | Dec 18 | Dec 25 | Dec 31 | Jan 1 | Jan 5 | Jan 12 | Jan 24 | Feb 23 |
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 | 241 | 233 | 226 | 220 | 214 | 209 | 204 | 197 | 189 |
| 32°F | 275 | 265 | 257 | 251 | 245 | 239 | 232 | 225 | 215 |
| 28°F | 315 | 302 | 294 | 287 | 280 | 273 | 266 | 256 | 246 |
| 24°F | 361 | 348 | 339 | 333 | 324 | 316 | 308 | 297 | 284 |
| 20°F | 365 | 365 | 365 | 365 | 362 | 354 | 345 | 335 | 317 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 352 |
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
- 96% of years
- 20°F or colder
- 53% of years
- 16°F or colder
- 18% 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
- 3,013
- Cooling degree days, base 65°F
- 2,295
- Growing degree days, base 40°F
- 8,512
- Growing degree days, base 45°F
- 6,894
- Growing degree days, base 50°F
- 5,457
- Growing degree days, base 55°F
- 4,234
- Growing degree days, base 60°F
- 3,186
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 668 | 0 | 10 |
| February | 512 | 0 | 30 |
| March | 373 | 2 | 140 |
| April | 181 | 31 | 309 |
| May | 43 | 208 | 631 |
| June | 3 | 450 | 897 |
| July | 0 | 632 | 1,097 |
| August | 0 | 566 | 1,031 |
| September | 7 | 329 | 772 |
| October | 113 | 76 | 430 |
| November | 425 | 1 | 102 |
| December | 688 | 0 | 8 |
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 18.6 km from Sandy Valley. 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 USC00263316 (Goodsprings). Public domain.