Hauser Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Coeur D'alene. 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 22 and the first fall freeze around October 18, a growing season of about 179 days.
- Median at 36°F
- last May 7, first October 6
- Median at 32°F
- last April 22, first October 18
- Median at 28°F
- last April 1, 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 21 | May 15 | May 12 | May 9 | May 7 | May 4 | May 1 | Apr 29 | Apr 25 |
| 32°F | May 6 | May 2 | Apr 29 | Apr 26 | Apr 22 | Apr 19 | Apr 14 | Apr 10 | Apr 4 |
| 28°F | Apr 21 | Apr 13 | Apr 7 | Apr 4 | Apr 1 | Mar 29 | Mar 24 | Mar 20 | Mar 13 |
| 24°F | Mar 29 | Mar 22 | Mar 19 | Mar 15 | Mar 12 | Mar 8 | Mar 5 | Mar 1 | Feb 23 |
| 20°F | Mar 16 | Mar 12 | Mar 8 | Mar 4 | Mar 1 | Feb 26 | Feb 21 | Feb 14 | Feb 3 |
| 16°F | Mar 9 | Mar 3 | Feb 28 | Feb 22 | Feb 15 | Feb 9 | Feb 2 | Jan 22 | Jan 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 | Sep 23 | Sep 28 | Oct 1 | Oct 3 | Oct 6 | Oct 9 | Oct 12 | Oct 16 | Oct 21 |
| 32°F | Oct 4 | Oct 8 | Oct 12 | Oct 15 | Oct 18 | Oct 22 | Oct 25 | Oct 30 | Nov 5 |
| 28°F | Oct 15 | Oct 21 | Oct 25 | Oct 29 | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 20 |
| 24°F | Oct 24 | Nov 1 | Nov 6 | Nov 9 | Nov 13 | Nov 18 | Nov 22 | Nov 26 | Dec 2 |
| 20°F | Nov 2 | Nov 10 | Nov 17 | Nov 23 | Nov 26 | Nov 30 | Dec 4 | Dec 11 | Dec 23 |
| 16°F | Nov 15 | Nov 25 | Nov 30 | Dec 4 | Dec 8 | Dec 16 | Dec 23 | Dec 30 | Jan 12 |
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 | 171 | 163 | 159 | 154 | 151 | 147 | 142 | 138 | 130 |
| 32°F | 202 | 194 | 188 | 184 | 179 | 175 | 170 | 165 | 158 |
| 28°F | 238 | 229 | 223 | 218 | 214 | 208 | 203 | 197 | 189 |
| 24°F | 274 | 264 | 258 | 252 | 246 | 241 | 236 | 230 | 221 |
| 20°F | 308 | 294 | 285 | 276 | 271 | 265 | 259 | 251 | 240 |
| 16°F | 342 | 328 | 318 | 308 | 301 | 291 | 282 | 273 | 262 |
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
- 6,317
- Cooling degree days, base 65°F
- 437
- Growing degree days, base 40°F
- 4,210
- Growing degree days, base 45°F
- 3,108
- Growing degree days, base 50°F
- 2,202
- Growing degree days, base 55°F
- 1,457
- Growing degree days, base 60°F
- 864
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,048 | 0 | 0 |
| February | 879 | 0 | 0 |
| March | 789 | 0 | 2 |
| April | 557 | 0 | 37 |
| May | 317 | 8 | 186 |
| June | 147 | 42 | 348 |
| July | 26 | 182 | 621 |
| August | 25 | 165 | 604 |
| September | 159 | 39 | 335 |
| October | 510 | 0 | 65 |
| November | 813 | 0 | 3 |
| December | 1,048 | 0 | 0 |
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 20 km from Hauser. 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 USC00101956 (Coeur D'alene). Public domain.