USDA Hardiness Zone 8a
Frost Dates for 79556 — Sweetwater, Texas
NOAA 1991–2020 normals from Roscoe, TX (2,380 ft), 8 miles west.
Updated
In Sweetwater, the last spring frost (32°F) is around March 30 in half of years and has passed by April 17 in nine years out of ten. The first fall frost comes around November 8, as early as October 26 one year in ten, leaving a typical freeze-free season of 223 days (NOAA, Roscoe, TX).
- Last spring frost
- March 30
- First fall frost
- November 8
- Growing season
- 223 days
- Hardiness zone
- 8a
50% probability
50% probability
freeze-free, 50%
10 to 15°F (-12.2 to -9.4°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 46%
- Snow per year
- 2.3"
median, 1991–2020
median, 1991–2020
13 of 28 observed
NOAA normal
Frost risk by date in Sweetwater
Half of springs at Roscoe, TX see their last 32°F night by March 30; only one in ten is past it by March 8, and one in ten still has one after April 17. Planting tender crops after April 4 leaves a 30% risk of a frost on them, after April 9 20%, and after April 17 10%. The 18 days between the even-odds date and the one-in-ten date is narrower than at 75% of the 339 Texas stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 8 in half of years, as early as October 26 one year in ten, and holds off past November 25 one year in ten. A hard freeze of 28°F follows 10 days later, around November 18; in spring the one-in-ten date for 28°F is April 4, 13 days before the 32°F one. The freeze-free season lasts 223 days in a typical year, shorter than at 83% of the 339 Texas stations; it reaches 249 days one year in ten and falls short of 201 one year in ten. On average 57 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 9 days longer, to about April 8, and return around October 30. Nights of 24°F, cold enough to damage hardier plants, come in 100% of winters and 16°F in 87%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Mar 22 | Mar 30 | Apr 3 | Apr 5 | Apr 8 | Apr 12 | Apr 16 | Apr 20 | Apr 27 |
| 32°F | Mar 8 | Mar 15 | Mar 21 | Mar 26 | Mar 30 | Apr 2 | Apr 4 | Apr 9 | Apr 17 |
| 28°F | Feb 25 | Mar 3 | Mar 8 | Mar 13 | Mar 16 | Mar 20 | Mar 25 | Mar 30 | Apr 4 |
| 24°F | Feb 8 | Feb 18 | Feb 24 | Feb 28 | Mar 4 | Mar 8 | Mar 12 | Mar 17 | Mar 25 |
| 20°F99% of yrs | Jan 17 | Jan 29 | Feb 5 | Feb 12 | Feb 18 | Feb 24 | Mar 1 | Mar 5 | Mar 12 |
| 16°F87% of yrs | Dec 30 | Jan 10 | Jan 19 | Jan 27 | Feb 1 | Feb 7 | Feb 14 | Feb 23 | Mar 4 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 17 | Oct 21 | Oct 24 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 12 |
| 32°F | Oct 26 | Nov 1 | Nov 3 | Nov 6 | Nov 8 | Nov 11 | Nov 15 | Nov 19 | Nov 25 |
| 28°F | Nov 1 | Nov 7 | Nov 11 | Nov 15 | Nov 18 | Nov 22 | Nov 26 | Dec 1 | Dec 4 |
| 24°F | Nov 10 | Nov 16 | Nov 21 | Nov 25 | Nov 29 | Dec 2 | Dec 5 | Dec 11 | Dec 20 |
| 20°F99% of yrs | Nov 20 | Nov 27 | Dec 2 | Dec 6 | Dec 12 | Dec 19 | Dec 28 | Jan 4 | Jan 15 |
| 16°F87% of yrs | Nov 30 | Dec 9 | Dec 16 | Dec 24 | Jan 1 | Jan 7 | Jan 14 | Jan 23 | Feb 4 |
Freeze probabilities 1991–2020 at Roscoe, TX, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 79556 →Compare Sweetwater with another place →
Weather by month in Sweetwater
July is the warmest month at Roscoe, TX, averaging 95°F by day and 71°F at night; January is the coldest at 56°F and 31°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 44% of years.
Warmth for growing adds up to 5,789 growing degree days a year (base 50°F), fewer than at 81% of the 351 Texas stations. 41% of them (2,351) have built up by the end of June, and July adds the most, 1,021. Precipitation totals 21.3 inches a year, most in June (3.1") and least in January (1.0"); May to September bring 56% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 56 | 31 | 1.0 | 100% | 18 | 40 |
| Feb | 60 | 34 | 1.0 | 100% | 11 | 81 |
| Mar | 69 | 42 | 1.4 | 93% | 6 | 225 |
| Apr | 78 | 50 | 1.5 | 44% | 1 | 425 |
| May | 85 | 60 | 2.8 | 1% | 0 | 693 |
| Jun | 91 | 68 | 3.1 | 0% | 0 | 886 |
| Jul | 95 | 71 | 1.8 | 0% | 0 | 1021 |
| Aug | 94 | 71 | 2.2 | 0% | 0 | 992 |
| Sep | 86 | 63 | 2.1 | 0% | 0 | 735 |
| Oct | 77 | 53 | 2.2 | 19% | 1 | 462 |
| Nov | 65 | 41 | 1.2 | 94% | 6 | 172 |
| Dec | 57 | 33 | 1.0 | 100% | 15 | 55 |
Monthly normals 1991–2020 at Roscoe, TX (2,380 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Merkel 12 SW, TX, 19 miles southeast of Sweetwater, has a last frost 3 days later (April 2), a first frost 5 days earlier (November 3), a season 8 days shorter.
When it snows in Sweetwater, Texas
Measurable snow is rare here: only 13 of 28 winters from 1991 to 2020 recorded 0.1 inch or more at Roscoe, TX, 7.6 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 79556
| When | What to do |
|---|---|
| January 19 – February 2 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 2 – February 16 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 2 – March 16 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| March 30 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 16 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 25 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 8 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 79556 is 8 miles from Roscoe, TX, which stands at 2,380 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 79556 in zone 8a, the band where the coldest night of the year averaged 10 to 15°F (-12.2 to -9.4°C) over 1991–2020; a zone describes winter lows, not frost dates.
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.