Gibson Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Little Rock. 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 16 and the first fall freeze around November 16, a growing season of about 245 days.
- Median at 36°F
- last March 28, first November 6
- Median at 32°F
- last March 16, first November 16
- Median at 28°F
- last March 4, first November 27
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 16 | Apr 8 | Apr 4 | Mar 31 | Mar 28 | Mar 25 | Mar 21 | Mar 17 | Mar 10 |
| 32°F | Apr 2 | Mar 28 | Mar 23 | Mar 18 | Mar 16 | Mar 12 | Mar 7 | Mar 3 | Feb 27 |
| 28°F | Mar 21 | Mar 15 | Mar 11 | Mar 7 | Mar 4 | Mar 1 | Feb 26 | Feb 22 | Feb 16 |
| 24°F | Mar 12 | Mar 6 | Mar 2 | Feb 27 | Feb 23 | Feb 18 | Feb 12 | Feb 6 | Jan 30 |
| 20°F | Mar 4 | Feb 25 | Feb 19 | Feb 13 | Feb 6 | Feb 1 | Jan 28 | Jan 22 | Jan 12 |
| 16°F | Feb 23 | Feb 14 | Feb 6 | Feb 1 | Jan 28 | Jan 22 | Jan 16 | Jan 9 | Dec 31 |
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 23 | Oct 29 | Oct 31 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 16 | Nov 21 |
| 32°F | Oct 31 | Nov 5 | Nov 10 | Nov 13 | Nov 16 | Nov 19 | Nov 23 | Nov 27 | Dec 2 |
| 28°F | Nov 10 | Nov 15 | Nov 20 | Nov 24 | Nov 27 | Dec 1 | Dec 4 | Dec 9 | Dec 17 |
| 24°F | Nov 21 | Nov 27 | Dec 1 | Dec 8 | Dec 12 | Dec 18 | Dec 23 | Dec 29 | Jan 6 |
| 20°F | Dec 2 | Dec 11 | Dec 18 | Dec 24 | Dec 29 | Jan 2 | Jan 7 | Jan 14 | Jan 25 |
| 16°F | Dec 13 | Dec 21 | Dec 28 | Jan 1 | Jan 6 | Jan 11 | Jan 15 | Jan 24 | Feb 5 |
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 | 246 | 238 | 233 | 227 | 222 | 218 | 213 | 208 | 200 |
| 32°F | 269 | 260 | 255 | 249 | 245 | 241 | 235 | 229 | 221 |
| 28°F | 296 | 286 | 279 | 273 | 268 | 262 | 258 | 252 | 241 |
| 24°F | 325 | 315 | 308 | 301 | 294 | 288 | 282 | 274 | 263 |
| 20°F | 353 | 342 | 334 | 327 | 321 | 316 | 309 | 301 | 289 |
| 16°F | 365 | 365 | 359 | 350 | 343 | 335 | 330 | 323 | 311 |
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
- 99% of years
- 20°F or colder
- 96% of years
- 16°F or colder
- 75% 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
- 3,145
- Cooling degree days, base 65°F
- 2,008
- Growing degree days, base 40°F
- 8,270
- Growing degree days, base 45°F
- 6,718
- Growing degree days, base 50°F
- 5,311
- Growing degree days, base 55°F
- 4,055
- Growing degree days, base 60°F
- 2,955
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 758 | 1 | 29 |
| February | 568 | 1 | 56 |
| March | 385 | 13 | 175 |
| April | 153 | 55 | 364 |
| May | 33 | 188 | 620 |
| June | 1 | 389 | 838 |
| July | 0 | 510 | 975 |
| August | 0 | 488 | 953 |
| September | 12 | 279 | 717 |
| October | 142 | 77 | 408 |
| November | 417 | 8 | 134 |
| December | 676 | 1 | 43 |
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 5.8 km from Gibson. 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 USW00003952 (Little Rock). Public domain.