Baird Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Putnam. 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 27 and the first fall freeze around November 7, a growing season of about 225 days.
- Median at 36°F
- last April 9, first October 30
- Median at 32°F
- last March 27, first November 7
- Median at 28°F
- last March 14, first November 16
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 25 | Apr 20 | Apr 16 | Apr 12 | Apr 9 | Apr 5 | Apr 1 | Mar 29 | Mar 22 |
| 32°F | Apr 16 | Apr 7 | Apr 3 | Mar 31 | Mar 27 | Mar 23 | Mar 19 | Mar 13 | Mar 7 |
| 28°F | Apr 2 | Mar 28 | Mar 23 | Mar 18 | Mar 14 | Mar 10 | Mar 6 | Mar 2 | Feb 25 |
| 24°F | Mar 22 | Mar 15 | Mar 11 | Mar 7 | Mar 3 | Feb 28 | Feb 24 | Feb 17 | Feb 7 |
| 20°F | Mar 11 | Mar 5 | Feb 28 | Feb 21 | Feb 15 | Feb 9 | Feb 2 | Jan 27 | Jan 17 |
| 16°F | Mar 1 | Feb 20 | Feb 12 | Feb 6 | Jan 30 | Jan 24 | Jan 17 | Jan 6 | Dec 28 |
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 17 | Oct 21 | Oct 25 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 12 |
| 32°F | Oct 25 | Oct 30 | Nov 2 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 22 |
| 28°F | Nov 1 | Nov 6 | Nov 9 | Nov 13 | Nov 16 | Nov 19 | Nov 24 | Nov 29 | Dec 4 |
| 24°F | Nov 9 | Nov 15 | Nov 21 | Nov 27 | Dec 1 | Dec 4 | Dec 9 | Dec 14 | Dec 22 |
| 20°F | Nov 21 | Nov 29 | Dec 3 | Dec 10 | Dec 16 | Dec 21 | Dec 27 | Jan 1 | Jan 11 |
| 16°F | Dec 1 | Dec 10 | Dec 18 | Dec 24 | Dec 30 | Jan 3 | Jan 9 | Jan 17 | Feb 2 |
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 | 227 | 219 | 212 | 208 | 204 | 199 | 195 | 189 | 183 |
| 32°F | 249 | 241 | 236 | 231 | 225 | 220 | 215 | 210 | 201 |
| 28°F | 273 | 264 | 257 | 253 | 247 | 242 | 237 | 230 | 221 |
| 24°F | 303 | 292 | 284 | 278 | 272 | 267 | 260 | 253 | 245 |
| 20°F | 339 | 328 | 318 | 310 | 304 | 296 | 290 | 281 | 271 |
| 16°F | 365 | 363 | 352 | 342 | 333 | 327 | 318 | 307 | 296 |
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
- 98% of years
- 16°F or colder
- 81% 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
- 2,606
- Cooling degree days, base 65°F
- 2,454
- Growing degree days, base 40°F
- 9,170
- Growing degree days, base 45°F
- 7,550
- Growing degree days, base 50°F
- 6,055
- Growing degree days, base 55°F
- 4,701
- Growing degree days, base 60°F
- 3,499
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 632 | 1 | 61 |
| February | 480 | 5 | 97 |
| March | 309 | 26 | 243 |
| April | 120 | 93 | 434 |
| May | 26 | 250 | 690 |
| June | 1 | 444 | 894 |
| July | 0 | 580 | 1,045 |
| August | 0 | 572 | 1,037 |
| September | 10 | 338 | 779 |
| October | 104 | 125 | 496 |
| November | 336 | 18 | 207 |
| December | 591 | 2 | 75 |
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 19.2 km from Baird. 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 USC00417327 (Putnam). Public domain.