North Ogden Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Ogden Ne Bench. 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 19 and the first fall freeze around October 22, a growing season of about 186 days.
- Median at 36°F
- last May 2, first October 12
- Median at 32°F
- last April 19, first October 22
- 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 20 | May 13 | May 8 | May 4 | May 2 | Apr 30 | Apr 26 | Apr 23 | Apr 18 |
| 32°F | May 4 | Apr 30 | Apr 26 | Apr 22 | Apr 19 | Apr 16 | Apr 12 | Apr 8 | Apr 2 |
| 28°F | Apr 20 | Apr 15 | Apr 11 | Apr 7 | Apr 2 | Mar 31 | Mar 25 | Mar 19 | Mar 12 |
| 24°F | Apr 7 | Mar 31 | Mar 25 | Mar 19 | Mar 15 | Mar 10 | Mar 7 | Mar 3 | Feb 25 |
| 20°F | Mar 16 | Mar 10 | Mar 7 | Mar 3 | Feb 28 | Feb 24 | Feb 19 | Feb 15 | Feb 8 |
| 16°F | Mar 4 | Feb 27 | Feb 21 | Feb 16 | Feb 12 | Feb 7 | Feb 3 | Jan 31 | Jan 20 |
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 29 | Oct 3 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 22 | Oct 25 |
| 32°F | Oct 7 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 5 |
| 28°F | Oct 18 | Oct 23 | Oct 26 | Oct 30 | Nov 1 | Nov 5 | Nov 8 | Nov 13 | Nov 18 |
| 24°F | Oct 26 | Nov 1 | Nov 5 | Nov 10 | Nov 13 | Nov 16 | Nov 20 | Nov 23 | Nov 27 |
| 20°F | Nov 6 | Nov 12 | Nov 16 | Nov 19 | Nov 22 | Nov 25 | Nov 28 | Dec 1 | Dec 8 |
| 16°F | Nov 14 | Nov 19 | Nov 24 | Nov 28 | Dec 1 | Dec 6 | Dec 11 | Dec 16 | Dec 24 |
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 | 182 | 175 | 170 | 166 | 162 | 158 | 154 | 149 | 139 |
| 32°F | 208 | 201 | 195 | 190 | 186 | 181 | 176 | 171 | 165 |
| 28°F | 236 | 227 | 221 | 216 | 212 | 207 | 202 | 196 | 188 |
| 24°F | 265 | 257 | 251 | 245 | 239 | 234 | 230 | 222 | 214 |
| 20°F | 291 | 283 | 278 | 272 | 267 | 262 | 256 | 249 | 239 |
| 16°F | 321 | 312 | 305 | 299 | 293 | 287 | 282 | 275 | 264 |
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
- 5,791
- Cooling degree days, base 65°F
- 871
- Growing degree days, base 40°F
- 5,221
- Growing degree days, base 45°F
- 4,037
- Growing degree days, base 50°F
- 3,024
- Growing degree days, base 55°F
- 2,173
- Growing degree days, base 60°F
- 1,459
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,099 | 0 | 0 |
| February | 857 | 0 | 2 |
| March | 702 | 0 | 18 |
| April | 490 | 2 | 72 |
| May | 228 | 30 | 284 |
| June | 61 | 133 | 524 |
| July | 4 | 329 | 790 |
| August | 4 | 291 | 751 |
| September | 108 | 82 | 434 |
| October | 422 | 5 | 133 |
| November | 755 | 0 | 16 |
| December | 1,063 | 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 7.1 km from North Ogden. 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 USC00426405 (Ogden Ne Bench). Public domain.