Texas County Frost Dates and Growing Season
Frost and the growing season
NOAA's 1991-2020 freeze probabilities for Houston. 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 10 and the first fall freeze around October 23, a growing season of about 194 days.
- Median at 36°F
- last April 25, first October 12
- Median at 32°F
- last April 10, first October 23
- Median at 28°F
- last March 29, first November 3
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 13 | May 7 | May 2 | Apr 29 | Apr 25 | Apr 21 | Apr 17 | Apr 13 | Apr 6 |
| 32°F | May 1 | Apr 24 | Apr 19 | Apr 14 | Apr 10 | Apr 7 | Apr 3 | Mar 30 | Mar 25 |
| 28°F | Apr 15 | Apr 8 | Apr 4 | Mar 31 | Mar 29 | Mar 26 | Mar 22 | Mar 18 | Mar 13 |
| 24°F | Apr 5 | Mar 30 | Mar 26 | Mar 22 | Mar 18 | Mar 15 | Mar 11 | Mar 6 | Mar 1 |
| 20°F | Mar 25 | Mar 18 | Mar 14 | Mar 9 | Mar 6 | Mar 3 | Feb 28 | Feb 22 | Feb 15 |
| 16°F | Mar 14 | Mar 9 | Mar 4 | Mar 1 | Feb 24 | Feb 19 | Feb 14 | Feb 9 | Feb 1 |
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 28 | Oct 3 | Oct 6 | Oct 10 | Oct 12 | Oct 15 | Oct 18 | Oct 21 | Oct 24 |
| 32°F | Oct 6 | Oct 13 | Oct 17 | Oct 20 | Oct 23 | Oct 25 | Oct 28 | Oct 31 | Nov 5 |
| 28°F | Oct 18 | Oct 23 | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 15 | Nov 23 |
| 24°F | Oct 31 | Nov 4 | Nov 7 | Nov 11 | Nov 15 | Nov 21 | Nov 25 | Nov 30 | Dec 5 |
| 20°F | Nov 8 | Nov 16 | Nov 21 | Nov 26 | Nov 30 | Dec 2 | Dec 6 | Dec 11 | Dec 18 |
| 16°F | Nov 22 | Nov 29 | Dec 2 | Dec 6 | Dec 11 | Dec 15 | Dec 20 | Dec 26 | Jan 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 | 192 | 184 | 178 | 173 | 169 | 164 | 160 | 155 | 146 |
| 32°F | 217 | 209 | 203 | 198 | 194 | 188 | 184 | 178 | 170 |
| 28°F | 245 | 235 | 230 | 224 | 218 | 214 | 209 | 203 | 193 |
| 24°F | 269 | 260 | 254 | 249 | 243 | 238 | 233 | 227 | 218 |
| 20°F | 294 | 285 | 277 | 273 | 266 | 261 | 256 | 250 | 241 |
| 16°F | 318 | 308 | 301 | 295 | 289 | 283 | 278 | 270 | 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
- 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
- 4,532
- Cooling degree days, base 65°F
- 1,256
- Growing degree days, base 40°F
- 6,562
- Growing degree days, base 45°F
- 5,206
- Growing degree days, base 50°F
- 4,001
- Growing degree days, base 55°F
- 2,942
- Growing degree days, base 60°F
- 2,026
Growing degree days by month, base 50°F
Heating and cooling by month
| Month | Heating DD | Cooling DD | Growing DD 50 |
|---|---|---|---|
| January | 979 | 0 | 7 |
| February | 766 | 0 | 20 |
| March | 589 | 5 | 85 |
| April | 285 | 27 | 238 |
| May | 103 | 96 | 461 |
| June | 11 | 248 | 687 |
| July | 1 | 370 | 834 |
| August | 4 | 332 | 793 |
| September | 60 | 149 | 540 |
| October | 282 | 28 | 253 |
| November | 572 | 2 | 70 |
| December | 879 | 0 | 13 |
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 0.3 km from Texas 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 USC00234019 (Houston). Public domain.