Fort Leonard Wood Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Ft Leonard Wood. 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 24, a growing season of about 193 days.
- Median at 36°F
- last April 27, first October 15
- Median at 32°F
- last April 14, first October 24
- Median at 28°F
- last April 2, first November 1
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 10 | May 5 | May 2 | Apr 30 | Apr 27 | Apr 24 | Apr 20 | Apr 16 | Apr 10 |
| 32°F | Apr 30 | Apr 25 | Apr 21 | Apr 17 | Apr 14 | Apr 11 | Apr 7 | Apr 3 | Mar 29 |
| 28°F | Apr 18 | Apr 13 | Apr 9 | Apr 5 | Apr 2 | Mar 31 | Mar 27 | Mar 23 | Mar 16 |
| 24°F | Apr 6 | Apr 1 | Mar 30 | Mar 26 | Mar 22 | Mar 18 | Mar 15 | Mar 8 | Mar 1 |
| 20°F | Mar 31 | Mar 24 | Mar 19 | Mar 15 | Mar 12 | Mar 7 | Mar 4 | Feb 28 | Feb 19 |
| 16°F | Mar 19 | Mar 14 | Mar 9 | Mar 5 | Mar 2 | Feb 26 | Feb 20 | Feb 12 | Feb 5 |
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 1 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 21 | Oct 23 | Oct 27 |
| 32°F | Oct 11 | Oct 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 29 | Nov 1 | Nov 6 |
| 28°F | Oct 21 | Oct 24 | Oct 28 | Oct 31 | Nov 1 | Nov 4 | Nov 7 | Nov 12 | Nov 17 |
| 24°F | Oct 30 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 19 | Nov 23 | Nov 29 |
| 20°F | Nov 5 | Nov 9 | Nov 14 | Nov 18 | Nov 22 | Nov 26 | Nov 30 | Dec 4 | Dec 11 |
| 16°F | Nov 12 | Nov 19 | Nov 25 | Nov 30 | Dec 3 | Dec 7 | Dec 12 | Dec 19 | Dec 25 |
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 | 191 | 183 | 178 | 174 | 170 | 166 | 161 | 157 | 150 |
| 32°F | 213 | 206 | 201 | 197 | 193 | 188 | 183 | 178 | 171 |
| 28°F | 237 | 229 | 223 | 219 | 215 | 210 | 206 | 201 | 194 |
| 24°F | 260 | 251 | 245 | 240 | 235 | 230 | 225 | 220 | 213 |
| 20°F | 282 | 273 | 267 | 263 | 257 | 252 | 246 | 240 | 231 |
| 16°F | 307 | 298 | 290 | 283 | 278 | 273 | 267 | 260 | 252 |
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
- 100% 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
- 4,728
- Cooling degree days, base 65°F
- 1,241
- Growing degree days, base 40°F
- 6,469
- Growing degree days, base 45°F
- 5,137
- Growing degree days, base 50°F
- 3,947
- Growing degree days, base 55°F
- 2,903
- Growing degree days, base 60°F
- 2,004
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,030 | 0 | 7 |
| February | 801 | 0 | 24 |
| March | 625 | 4 | 75 |
| April | 307 | 19 | 212 |
| May | 111 | 90 | 448 |
| June | 7 | 239 | 682 |
| July | 1 | 375 | 840 |
| August | 2 | 331 | 793 |
| September | 52 | 148 | 546 |
| October | 284 | 33 | 253 |
| November | 601 | 2 | 56 |
| December | 908 | 0 | 10 |
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 6.5 km from Fort Leonard Wood. 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 USC00232981 (Ft Leonard Wood). Public domain.