Lander County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Beowawe 49S - U Of N Rch. 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 May 28 and the first fall freeze around September 21, a growing season of about 114 days.
- Median at 36°F
- last June 11, first September 9
- Median at 32°F
- last May 28, first September 21
- Median at 28°F
- last May 12, first October 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 | Jun 26 | Jun 21 | Jun 18 | Jun 14 | Jun 11 | Jun 8 | Jun 4 | Jun 1 | May 26 |
| 32°F | Jun 16 | Jun 9 | Jun 5 | Jun 1 | May 28 | May 24 | May 20 | May 16 | May 11 |
| 28°F | Jun 1 | May 25 | May 19 | May 15 | May 12 | May 9 | May 4 | May 1 | Apr 27 |
| 24°F | May 14 | May 9 | May 4 | May 1 | Apr 28 | Apr 25 | Apr 21 | Apr 17 | Apr 11 |
| 20°F | Apr 30 | Apr 24 | Apr 19 | Apr 15 | Apr 11 | Apr 7 | Apr 2 | Mar 28 | Mar 16 |
| 16°F | Apr 12 | Apr 5 | Mar 31 | Mar 24 | Mar 18 | Mar 13 | Mar 7 | Mar 2 | Feb 23 |
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 | Aug 26 | Sep 1 | Sep 3 | Sep 6 | Sep 9 | Sep 12 | Sep 15 | Sep 19 | Sep 22 |
| 32°F | Sep 6 | Sep 10 | Sep 15 | Sep 18 | Sep 21 | Sep 24 | Sep 26 | Sep 29 | Oct 3 |
| 28°F | Sep 18 | Sep 23 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 6 | Oct 9 | Oct 14 |
| 24°F | Sep 27 | Sep 30 | Oct 3 | Oct 7 | Oct 10 | Oct 13 | Oct 16 | Oct 19 | Oct 24 |
| 20°F | Oct 5 | Oct 10 | Oct 14 | Oct 16 | Oct 19 | Oct 23 | Oct 26 | Oct 30 | Nov 4 |
| 16°F | Oct 14 | Oct 19 | Oct 23 | Oct 27 | Oct 31 | Nov 3 | Nov 7 | Nov 12 | Nov 19 |
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 | 109 | 103 | 97 | 93 | 89 | 85 | 81 | 75 | 69 |
| 32°F | 137 | 130 | 124 | 120 | 114 | 109 | 105 | 99 | 91 |
| 28°F | 161 | 155 | 149 | 144 | 140 | 136 | 130 | 125 | 116 |
| 24°F | 188 | 180 | 174 | 170 | 165 | 160 | 156 | 150 | 142 |
| 20°F | 220 | 210 | 204 | 199 | 192 | 187 | 181 | 175 | 166 |
| 16°F | 254 | 244 | 236 | 230 | 224 | 218 | 212 | 203 | 193 |
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
- 6,613
- Cooling degree days, base 65°F
- 406
- Growing degree days, base 40°F
- 4,186
- Growing degree days, base 45°F
- 3,077
- Growing degree days, base 50°F
- 2,169
- Growing degree days, base 55°F
- 1,437
- Growing degree days, base 60°F
- 849
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 1,118 | 0 | 0 |
| February | 896 | 0 | 1 |
| March | 786 | 0 | 5 |
| April | 615 | 0 | 30 |
| May | 369 | 4 | 160 |
| June | 133 | 52 | 377 |
| July | 12 | 195 | 648 |
| August | 24 | 132 | 574 |
| September | 180 | 22 | 304 |
| October | 524 | 0 | 67 |
| November | 822 | 0 | 5 |
| December | 1,136 | 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 38.6 km from Lander County. 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 USC00260800 (Beowawe 49S - U Of N Rch). Public domain.