Maverick County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Eagle Pass 3N. 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 February 19 and the first fall freeze around December 1, a growing season of about 287 days.
- Median at 36°F
- last March 2, first November 20
- Median at 32°F
- last February 19, first December 1
- Median at 28°F
- last January 31, first December 14
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 | Mar 20 | Mar 15 | Mar 9 | Mar 5 | Mar 2 | Feb 28 | Feb 23 | Feb 19 | Feb 12 |
| 32°F | Mar 10 | Mar 2 | Feb 28 | Feb 23 | Feb 19 | Feb 15 | Feb 9 | Jan 31 | Jan 22 |
| 28°F | Mar 1 | Feb 21 | Feb 14 | Feb 7 | Jan 31 | Jan 23 | Jan 14 | Jan 5 | Dec 25 |
| 24°F | Feb 17 | Feb 9 | Feb 1 | Jan 20 | Jan 10 | Jan 4 | Dec 30 | Dec 24 | Dec 13 |
| 20°F | Feb 10 | Feb 1 | Jan 12 | Jan 5 | Dec 31 | Dec 28 | Dec 23 | Dec 16 | Dec 11 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 | Nov 4 | Nov 9 | Nov 13 | Nov 17 | Nov 20 | Nov 24 | Nov 27 | Nov 30 | Dec 5 |
| 32°F | Nov 14 | Nov 20 | Nov 25 | Nov 29 | Dec 1 | Dec 4 | Dec 8 | Dec 14 | Dec 23 |
| 28°F | Nov 26 | Dec 1 | Dec 5 | Dec 10 | Dec 14 | Dec 20 | Dec 26 | Jan 3 | Jan 20 |
| 24°F | Dec 4 | Dec 9 | Dec 14 | Dec 21 | Dec 26 | Jan 1 | Jan 7 | Jan 20 | Feb 6 |
| 20°F | Dec 9 | Dec 14 | Dec 19 | Dec 24 | Dec 29 | Jan 1 | Jan 7 | Jan 23 | Feb 8 |
| 16°F | – | – | – | – | – | – | – | – | – |
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 | 288 | 279 | 273 | 267 | 262 | 257 | 250 | 244 | 234 |
| 32°F | 321 | 311 | 301 | 294 | 287 | 281 | 275 | 267 | 257 |
| 28°F | 360 | 347 | 340 | 334 | 324 | 317 | 309 | 299 | 285 |
| 24°F | 365 | 365 | 365 | 365 | 358 | 349 | 341 | 333 | 320 |
| 20°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 364 | 350 |
| 16°F | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 | 365 |
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
- 94% of years
- 24°F or colder
- 59% of years
- 20°F or colder
- 22% of years
- 16°F or colder
- 4% 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
- 1,400
- Cooling degree days, base 65°F
- 3,339
- Growing degree days, base 40°F
- 11,085
- Growing degree days, base 45°F
- 9,307
- Growing degree days, base 50°F
- 7,604
- Growing degree days, base 55°F
- 6,023
- Growing degree days, base 60°F
- 4,597
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 404 | 4 | 137 |
| February | 249 | 17 | 219 |
| March | 110 | 95 | 456 |
| April | 23 | 205 | 632 |
| May | 3 | 409 | 871 |
| June | 0 | 567 | 1,017 |
| July | 0 | 640 | 1,105 |
| August | 0 | 665 | 1,130 |
| September | 1 | 465 | 914 |
| October | 30 | 227 | 663 |
| November | 182 | 43 | 326 |
| December | 397 | 4 | 134 |
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 16.2 km from Maverick 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 USC00412679 (Eagle Pass 3N). Public domain.