Avenal Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Kettleman City. 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 February 19 and the first fall freeze around November 29, a growing season of about 281 days.
- Median at 36°F
- last March 17, first November 15
- Median at 32°F
- last February 19, first November 29
- Median at 28°F
- last January 24, first December 12
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 8 | Apr 2 | Mar 27 | Mar 22 | Mar 17 | Mar 12 | Mar 6 | Feb 28 | Feb 20 |
| 32°F | Mar 15 | Mar 8 | Mar 2 | Feb 26 | Feb 19 | Feb 13 | Feb 7 | Jan 31 | Jan 21 |
| 28°F | Feb 23 | Feb 11 | Feb 4 | Jan 31 | Jan 24 | Jan 18 | Jan 11 | Jan 3 | Dec 26 |
| 24°F | Jan 31 | Jan 24 | Jan 13 | Jan 7 | Jan 2 | Dec 31 | Dec 26 | Dec 21 | Dec 15 |
| 20°F | Jan 16 | Jan 11 | Jan 5 | Jan 1 | Dec 31 | Dec 29 | Dec 25 | Dec 22 | Dec 17 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 31 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 25 | Nov 30 |
| 32°F | Nov 14 | Nov 18 | Nov 23 | Nov 25 | Nov 29 | Dec 1 | Dec 4 | Dec 9 | Dec 17 |
| 28°F | Nov 25 | Dec 1 | Dec 4 | Dec 8 | Dec 12 | Dec 18 | Dec 23 | Jan 2 | Jan 15 |
| 24°F | Dec 4 | Dec 9 | Dec 14 | Dec 19 | Dec 22 | Dec 28 | Jan 1 | Jan 7 | Jan 16 |
| 20°F | Dec 10 | Dec 16 | Dec 21 | Dec 24 | Dec 28 | Dec 30 | Jan 1 | Jan 6 | Jan 14 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 | 271 | 260 | 254 | 247 | 242 | 237 | 230 | 223 | 215 |
| 32°F | 314 | 302 | 295 | 287 | 281 | 274 | 268 | 261 | 252 |
| 28°F | 357 | 346 | 337 | 330 | 324 | 317 | 309 | 300 | 289 |
| 24°F | 365 | 365 | 365 | 365 | 363 | 355 | 348 | 339 | 333 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 357 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 |
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
- 93% of years
- 24°F or colder
- 49% of years
- 20°F or colder
- 14% of years
- 16°F or colder
- 2% 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
- 2,368
- Cooling degree days, base 65°F
- 2,134
- Growing degree days, base 40°F
- 8,905
- Growing degree days, base 45°F
- 7,167
- Growing degree days, base 50°F
- 5,598
- Growing degree days, base 55°F
- 4,239
- Growing degree days, base 60°F
- 3,091
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 580 | 0 | 19 |
| February | 380 | 0 | 83 |
| March | 270 | 5 | 214 |
| April | 141 | 44 | 354 |
| May | 32 | 184 | 617 |
| June | 3 | 364 | 812 |
| July | 0 | 561 | 1,026 |
| August | 0 | 522 | 987 |
| September | 4 | 345 | 792 |
| October | 62 | 105 | 509 |
| November | 325 | 3 | 155 |
| December | 572 | 0 | 30 |
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 15.2 km from Avenal. 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 USC00044534 (Kettleman City). Public domain.