Lecompte Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Lsu Dean Lee Rsch Stn. 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 1 and the first fall freeze around November 22, a growing season of about 267 days.
- Median at 36°F
- last March 16, first November 8
- Median at 32°F
- last March 1, first November 22
- Median at 28°F
- last February 10, first December 7
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 6 | Mar 31 | Mar 25 | Mar 20 | Mar 16 | Mar 12 | Mar 7 | Mar 2 | Feb 24 |
| 32°F | Mar 22 | Mar 15 | Mar 10 | Mar 5 | Mar 1 | Feb 26 | Feb 20 | Feb 15 | Feb 1 |
| 28°F | Mar 9 | Mar 2 | Feb 26 | Feb 18 | Feb 10 | Feb 3 | Jan 29 | Jan 23 | Jan 10 |
| 24°F | Feb 25 | Feb 11 | Feb 2 | Jan 30 | Jan 25 | Jan 19 | Jan 12 | Jan 4 | Dec 25 |
| 20°F | Feb 6 | Jan 31 | Jan 25 | Jan 21 | Jan 15 | Jan 10 | Jan 6 | Dec 31 | Dec 24 |
| 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 23 | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 16 | Nov 21 | Nov 29 |
| 32°F | Nov 2 | Nov 8 | Nov 13 | Nov 18 | Nov 22 | Nov 26 | Dec 1 | Dec 4 | Dec 13 |
| 28°F | Nov 14 | Nov 23 | Nov 28 | Dec 3 | Dec 7 | Dec 14 | Dec 23 | Jan 1 | Jan 11 |
| 24°F | Nov 30 | Dec 8 | Dec 17 | Dec 24 | Dec 31 | Jan 3 | Jan 9 | Jan 19 | Feb 1 |
| 20°F | Dec 13 | Dec 25 | Jan 1 | Jan 2 | Jan 6 | Jan 10 | Jan 16 | Jan 23 | Feb 1 |
| 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 | 265 | 255 | 248 | 242 | 236 | 231 | 225 | 220 | 209 |
| 32°F | 300 | 288 | 280 | 274 | 267 | 261 | 255 | 248 | 237 |
| 28°F | 339 | 327 | 319 | 310 | 304 | 295 | 287 | 277 | 267 |
| 24°F | 365 | 365 | 358 | 349 | 342 | 335 | 329 | 317 | 306 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 363 | 352 | 339 |
| 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
- 100% of years
- 28°F or colder
- 97% of years
- 24°F or colder
- 74% of years
- 20°F or colder
- 31% of years
- 16°F or colder
- 7% 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
- 1,869
- Cooling degree days, base 65°F
- 2,605
- Growing degree days, base 40°F
- 9,909
- Growing degree days, base 45°F
- 8,181
- Growing degree days, base 50°F
- 6,556
- Growing degree days, base 55°F
- 5,072
- Growing degree days, base 60°F
- 3,752
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 489 | 6 | 110 |
| February | 340 | 12 | 154 |
| March | 206 | 37 | 316 |
| April | 71 | 114 | 494 |
| May | 6 | 303 | 763 |
| June | 0 | 466 | 916 |
| July | 0 | 549 | 1,014 |
| August | 0 | 550 | 1,015 |
| September | 3 | 383 | 831 |
| October | 66 | 148 | 549 |
| November | 245 | 26 | 259 |
| December | 443 | 11 | 136 |
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 9.3 km from Lecompte. 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 USC00165630 (Lsu Dean Lee Rsch Stn). Public domain.