Arvin Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Bakersfield AP. 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 January 17 and the first fall freeze around December 15, a growing season of about 334 days.
- Median at 36°F
- last February 21, first December 1
- Median at 32°F
- last January 17, first December 15
- Median at 28°F
- last January 2, first December 24
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 | Mar 26 | Mar 12 | Mar 3 | Feb 27 | Feb 21 | Feb 12 | Feb 5 | Jan 31 | Jan 19 |
| 32°F | Feb 18 | Feb 5 | Jan 31 | Jan 24 | Jan 17 | Jan 12 | Jan 6 | Dec 31 | Dec 23 |
| 28°F | Jan 23 | Jan 14 | Jan 10 | Jan 6 | Jan 2 | Dec 31 | Dec 27 | Dec 21 | Dec 14 |
| 24°F | – | – | – | – | – | – | – | – | – |
| 20°F | – | – | – | – | – | – | – | – | – |
| 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 | Nov 16 | Nov 22 | Nov 25 | Nov 29 | Dec 1 | Dec 4 | Dec 7 | Dec 12 | Dec 20 |
| 32°F | Nov 30 | Dec 3 | Dec 7 | Dec 11 | Dec 15 | Dec 19 | Dec 26 | Jan 2 | Jan 12 |
| 28°F | Dec 7 | Dec 12 | Dec 16 | Dec 21 | Dec 24 | Dec 30 | Jan 2 | Jan 8 | Jan 13 |
| 24°F | – | – | – | – | – | – | – | – | – |
| 20°F | – | – | – | – | – | – | – | – | – |
| 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 | 319 | 307 | 298 | 292 | 284 | 276 | 269 | 259 | 248 |
| 32°F | 361 | 350 | 344 | 338 | 334 | 328 | 322 | 311 | 301 |
| 28°F | 365 | 365 | 365 | 365 | 365 | 363 | 355 | 347 | 339 |
| 24°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 |
| 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
- 90% of years
- 28°F or colder
- 41% of years
- 24°F or colder
- 8% of years
- 20°F or colder
- 0% of years
- 16°F or colder
- 0% 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
- 1,958
- Cooling degree days, base 65°F
- 2,425
- Growing degree days, base 40°F
- 9,597
- Growing degree days, base 45°F
- 7,812
- Growing degree days, base 50°F
- 6,145
- Growing degree days, base 55°F
- 4,677
- Growing degree days, base 60°F
- 3,442
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 481 | 0 | 61 |
| February | 316 | 1 | 127 |
| March | 211 | 13 | 272 |
| April | 113 | 62 | 400 |
| May | 26 | 214 | 653 |
| June | 2 | 413 | 861 |
| July | 0 | 614 | 1,079 |
| August | 0 | 572 | 1,037 |
| September | 1 | 397 | 846 |
| October | 49 | 133 | 549 |
| November | 269 | 6 | 203 |
| December | 490 | 0 | 58 |
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 32.4 km from Arvin. 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 USW00023155 (Bakersfield AP). Public domain.