Farwell Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Clovis. 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 14 and the first fall freeze around October 29, a growing season of about 197 days.
- Median at 36°F
- last April 24, first October 19
- Median at 32°F
- last April 14, first October 29
- Median at 28°F
- last April 2, first November 8
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 6 | May 2 | Apr 30 | Apr 27 | Apr 24 | Apr 22 | Apr 19 | Apr 17 | Apr 12 |
| 32°F | Apr 26 | Apr 22 | Apr 19 | Apr 16 | Apr 14 | Apr 10 | Apr 6 | Apr 2 | Mar 28 |
| 28°F | Apr 17 | Apr 12 | Apr 7 | Apr 4 | Apr 2 | Mar 29 | Mar 25 | Mar 19 | Mar 12 |
| 24°F | Apr 4 | Mar 31 | Mar 25 | Mar 19 | Mar 15 | Mar 11 | Mar 7 | Mar 3 | Feb 25 |
| 20°F | Mar 21 | Mar 14 | Mar 9 | Mar 5 | Mar 2 | Feb 27 | Feb 22 | Feb 18 | Feb 9 |
| 16°F | Mar 10 | Mar 3 | Feb 26 | Feb 21 | Feb 15 | Feb 8 | Feb 1 | Jan 24 | Jan 8 |
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 5 | Oct 10 | Oct 14 | Oct 17 | Oct 19 | Oct 21 | Oct 23 | Oct 27 | Oct 30 |
| 32°F | Oct 17 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 10 |
| 28°F | Oct 26 | Oct 31 | Nov 3 | Nov 5 | Nov 8 | Nov 10 | Nov 13 | Nov 16 | Nov 20 |
| 24°F | Nov 1 | Nov 6 | Nov 10 | Nov 13 | Nov 16 | Nov 19 | Nov 22 | Nov 26 | Dec 1 |
| 20°F | Nov 9 | Nov 15 | Nov 19 | Nov 22 | Nov 26 | Nov 30 | Dec 4 | Dec 9 | Dec 16 |
| 16°F | Nov 17 | Nov 24 | Nov 30 | Dec 5 | Dec 11 | Dec 17 | Dec 23 | Dec 29 | Jan 8 |
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 | 193 | 189 | 184 | 180 | 177 | 174 | 170 | 166 | 159 |
| 32°F | 217 | 211 | 206 | 201 | 197 | 194 | 191 | 186 | 178 |
| 28°F | 243 | 235 | 229 | 224 | 220 | 215 | 212 | 206 | 199 |
| 24°F | 269 | 261 | 255 | 251 | 246 | 240 | 234 | 228 | 221 |
| 20°F | 299 | 288 | 281 | 274 | 269 | 263 | 259 | 251 | 242 |
| 16°F | 342 | 327 | 317 | 309 | 303 | 296 | 288 | 279 | 265 |
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
- 98% 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
- 3,731
- Cooling degree days, base 65°F
- 1,510
- Growing degree days, base 40°F
- 7,275
- Growing degree days, base 45°F
- 5,784
- Growing degree days, base 50°F
- 4,459
- Growing degree days, base 55°F
- 3,308
- Growing degree days, base 60°F
- 2,328
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 795 | 0 | 12 |
| February | 613 | 0 | 26 |
| March | 462 | 2 | 114 |
| April | 246 | 18 | 255 |
| May | 70 | 126 | 524 |
| June | 2 | 343 | 790 |
| July | 1 | 428 | 893 |
| August | 1 | 377 | 841 |
| September | 32 | 186 | 606 |
| October | 213 | 28 | 306 |
| November | 526 | 1 | 79 |
| December | 770 | 0 | 14 |
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 15.6 km from Farwell. 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 USC00291939 (Clovis). Public domain.