Elverta Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Sacramento Metro 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 February 22 and the first fall freeze around November 24, a growing season of about 277 days.
- Median at 36°F
- last April 1, first November 10
- Median at 32°F
- last February 22, first November 24
- Median at 28°F
- last January 17, first December 10
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 22 | Apr 15 | Apr 9 | Apr 4 | Apr 1 | Mar 27 | Mar 19 | Mar 12 | Mar 2 |
| 32°F | Apr 1 | Mar 17 | Mar 5 | Feb 28 | Feb 22 | Feb 14 | Feb 4 | Jan 27 | Jan 10 |
| 28°F | Feb 19 | Feb 7 | Jan 31 | Jan 24 | Jan 17 | Jan 7 | Dec 31 | Dec 26 | Dec 17 |
| 24°F | Jan 28 | Jan 18 | Jan 11 | Jan 2 | Dec 30 | Dec 26 | Dec 22 | Dec 17 | Dec 10 |
| 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 | Oct 24 | Oct 30 | Nov 2 | Nov 6 | Nov 10 | Nov 12 | Nov 16 | Nov 19 | Nov 25 |
| 32°F | Nov 9 | Nov 13 | Nov 17 | Nov 21 | Nov 24 | Nov 28 | Dec 1 | Dec 6 | Dec 21 |
| 28°F | Nov 21 | Nov 29 | Dec 2 | Dec 6 | Dec 10 | Dec 15 | Dec 24 | Jan 3 | Jan 18 |
| 24°F | Dec 1 | Dec 6 | Dec 12 | Dec 15 | Dec 19 | Dec 24 | Jan 1 | Jan 6 | Jan 16 |
| 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 | 256 | 245 | 236 | 231 | 224 | 218 | 212 | 206 | 197 |
| 32°F | 324 | 307 | 296 | 285 | 277 | 269 | 260 | 250 | 236 |
| 28°F | 365 | 360 | 350 | 341 | 335 | 331 | 322 | 312 | 299 |
| 24°F | 365 | 365 | 365 | 365 | 365 | 365 | 360 | 350 | 339 |
| 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
- 99% of years
- 28°F or colder
- 81% of years
- 24°F or colder
- 35% of years
- 20°F or colder
- 6% 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
- 2,644
- Cooling degree days, base 65°F
- 1,279
- Growing degree days, base 40°F
- 7,773
- Growing degree days, base 45°F
- 6,032
- Growing degree days, base 50°F
- 4,482
- Growing degree days, base 55°F
- 3,185
- Growing degree days, base 60°F
- 2,125
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 572 | 0 | 18 |
| February | 410 | 0 | 59 |
| March | 330 | 0 | 152 |
| April | 199 | 15 | 269 |
| May | 60 | 98 | 502 |
| June | 8 | 231 | 674 |
| July | 0 | 350 | 815 |
| August | 0 | 321 | 786 |
| September | 8 | 212 | 654 |
| October | 99 | 51 | 417 |
| November | 371 | 1 | 116 |
| December | 586 | 0 | 20 |
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 11.2 km from Elverta. 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 USW00093225 (Sacramento Metro AP). Public domain.