Brookland Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Jonesboro 2 Ne. 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 1 and the first fall freeze around November 1, a growing season of about 215 days.
- Median at 36°F
- last April 12, first October 23
- Median at 32°F
- last April 1, first November 1
- Median at 28°F
- last March 20, first November 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 30 | Apr 24 | Apr 19 | Apr 15 | Apr 12 | Apr 9 | Apr 6 | Apr 2 | Mar 27 |
| 32°F | Apr 18 | Apr 11 | Apr 7 | Apr 5 | Apr 1 | Mar 29 | Mar 25 | Mar 21 | Mar 15 |
| 28°F | Apr 6 | Apr 1 | Mar 28 | Mar 23 | Mar 20 | Mar 16 | Mar 13 | Mar 7 | Mar 1 |
| 24°F | Mar 27 | Mar 20 | Mar 16 | Mar 12 | Mar 8 | Mar 4 | Feb 28 | Feb 25 | Feb 18 |
| 20°F | Mar 17 | Mar 12 | Mar 6 | Mar 2 | Feb 28 | Feb 22 | Feb 16 | Feb 9 | Jan 31 |
| 16°F | Mar 10 | Mar 2 | Feb 25 | Feb 18 | Feb 12 | Feb 5 | Jan 31 | Jan 25 | Jan 13 |
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 12 | Oct 16 | Oct 19 | Oct 21 | Oct 23 | Oct 25 | Oct 28 | Oct 30 | Nov 3 |
| 32°F | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 16 |
| 28°F | Oct 29 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 15 | Nov 19 | Nov 24 | Dec 1 |
| 24°F | Nov 4 | Nov 9 | Nov 14 | Nov 18 | Nov 22 | Nov 26 | Dec 1 | Dec 5 | Dec 13 |
| 20°F | Nov 13 | Nov 21 | Nov 27 | Dec 1 | Dec 5 | Dec 10 | Dec 18 | Dec 25 | Jan 1 |
| 16°F | Nov 28 | Dec 5 | Dec 11 | Dec 20 | Dec 25 | Dec 30 | Jan 2 | Jan 8 | Jan 17 |
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 | 214 | 206 | 202 | 199 | 194 | 190 | 186 | 181 | 173 |
| 32°F | 238 | 229 | 224 | 219 | 215 | 211 | 206 | 201 | 193 |
| 28°F | 262 | 253 | 247 | 241 | 237 | 232 | 228 | 223 | 215 |
| 24°F | 285 | 276 | 270 | 264 | 259 | 254 | 248 | 242 | 234 |
| 20°F | 317 | 305 | 297 | 290 | 284 | 278 | 270 | 263 | 254 |
| 16°F | 342 | 333 | 325 | 319 | 311 | 305 | 298 | 290 | 278 |
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
- 3,877
- Cooling degree days, base 65°F
- 1,686
- Growing degree days, base 40°F
- 7,435
- Growing degree days, base 45°F
- 5,998
- Growing degree days, base 50°F
- 4,706
- Growing degree days, base 55°F
- 3,557
- Growing degree days, base 60°F
- 2,550
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 894 | 0 | 15 |
| February | 691 | 0 | 27 |
| March | 501 | 5 | 110 |
| April | 211 | 37 | 298 |
| May | 54 | 153 | 565 |
| June | 2 | 351 | 799 |
| July | 0 | 454 | 919 |
| August | 0 | 419 | 883 |
| September | 22 | 217 | 645 |
| October | 195 | 48 | 335 |
| November | 514 | 4 | 88 |
| December | 795 | 0 | 22 |
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 9 km from Brookland. 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 USC00033734 (Jonesboro 2 Ne). Public domain.