USDA Hardiness Zone 9a
Frost Dates for 78757 — Austin, Texas
NOAA 1991–2020 normals from Austin-Camp Mabry, TX (670 ft), 3 miles southwest.
Updated
In Austin, the last spring frost (32°F) is around February 20 in half of years and has passed by March 14 in nine years out of ten. The first fall frost comes around December 3, as early as November 15 one year in ten, leaving a typical freeze-free season of 291 days (NOAA, Austin-Camp Mabry, TX).
- Last spring frost
- February 20
- First fall frost
- December 3
- Growing season
- 291 days
- Hardiness zone
- 9a
50% probability
50% probability
freeze-free, 50%
20 to 25°F (-6.7 to -3.9°C) coldest night
- First snow
- Rare
- Last snow
- Rare
- Winters with snow
- 33%
- Snow per year
- 0.2"
median, 1991–2020
median, 1991–2020
10 of 30 observed
NOAA normal
Frost risk by date in Austin
Half of springs at Austin-Camp Mabry, TX see their last 32°F night by February 20; only one in ten is past it by January 23, and one in ten still has one after March 14. Planting tender crops after March 2 leaves a 30% risk of a frost on them, after March 7 20%, and after March 14 10%. The 22 days between the even-odds date and the one-in-ten date is wider than at 63% of the 339 Texas stations behind this site's ZIP pages, so a fixed calendar date is a gamble here.
In fall the first 32°F night comes by December 3 in half of years, as early as November 15 one year in ten, and holds off past January 1 one year in ten. A hard freeze of 28°F follows 24 days later, around December 27; in spring the one-in-ten date for 28°F is March 3, 11 days before the 32°F one. The freeze-free season lasts 291 days in a typical year, longer than at 83% of the 339 Texas stations; it reaches 326 days one year in ten and falls short of 258 one year in ten. On average 12 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 14 days longer, to about March 6, and return around November 22. A 24°F night is unusual: 46% of winters had one.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Feb 14 | Feb 22 | Feb 27 | Mar 3 | Mar 6 | Mar 11 | Mar 15 | Mar 19 | Mar 27 |
| 32°F99% of yrs | Jan 23 | Feb 1 | Feb 9 | Feb 15 | Feb 20 | Feb 26 | Mar 2 | Mar 7 | Mar 14 |
| 28°F88% of yrs | Dec 29 | Jan 11 | Jan 20 | Jan 27 | Feb 1 | Feb 6 | Feb 13 | Feb 21 | Mar 3 |
| 24°F46% of yrs | too rare for a date | ||||||||
| 20°F10% of yrs | too rare for a date | ||||||||
| 16°F1% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 5 | Nov 10 | Nov 15 | Nov 18 | Nov 22 | Nov 26 | Nov 29 | Dec 3 | Dec 10 |
| 32°F99% of yrs | Nov 15 | Nov 21 | Nov 26 | Nov 30 | Dec 3 | Dec 8 | Dec 13 | Dec 23 | Jan 1 |
| 28°F88% of yrs | Nov 27 | Dec 3 | Dec 10 | Dec 18 | Dec 27 | Jan 1 | Jan 6 | Jan 15 | Feb 1 |
| 24°F46% of yrs | too rare for a date | ||||||||
| 20°F10% of yrs | too rare for a date | ||||||||
| 16°F1% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Austin-Camp Mabry, 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 78757 →Compare Austin with another place →
Weather by month in Austin
August is the warmest month at Austin-Camp Mabry, TX, averaging 98°F by day and 75°F at night; January is the coldest at 63°F and 42°F. From April to October the chance of a 32°F night stays under 10% each month. In spring, February still brings one in 68% of years and March still brings one in 34% of years.
Warmth for growing adds up to 7,547 growing degree days a year (base 50°F), more than at 79% of the 351 Texas stations. 42% of them (3,186) have built up by the end of June, and August adds the most, 1,130. Precipitation totals 36.2 inches a year, most in May (5.0") and least in February (1.9"); May to September bring 47% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 63 | 42 | 2.6 | 87% | 5 | 151 |
| Feb | 67 | 46 | 1.9 | 68% | 2 | 215 |
| Mar | 73 | 52 | 2.9 | 34% | 1 | 408 |
| Apr | 80 | 59 | 2.4 | 0% | 0 | 589 |
| May | 87 | 67 | 5.0 | 0% | 0 | 832 |
| Jun | 93 | 73 | 3.7 | 0% | 0 | 991 |
| Jul | 97 | 75 | 2.0 | 0% | 0 | 1110 |
| Aug | 98 | 75 | 2.7 | 0% | 0 | 1130 |
| Sep | 91 | 70 | 3.5 | 0% | 0 | 923 |
| Oct | 83 | 61 | 3.9 | 0% | 0 | 672 |
| Nov | 72 | 51 | 2.9 | 41% | 1 | 350 |
| Dec | 64 | 43 | 2.7 | 82% | 3 | 177 |
Monthly normals 1991–2020 at Austin-Camp Mabry, TX (670 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, Austin Great Hills, TX, 5 miles northwest of Austin and 210 feet higher, has a last frost 19 days later (March 11), a first frost 13 days earlier (November 20), a season 37 days shorter.
When it snows in Austin, Texas
Measurable snow is rare here: only 10 of 30 winters from 1991 to 2020 recorded 0.1 inch or more at Austin-Camp Mabry, TX, 2.6 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 78757
| When | What to do |
|---|---|
| December 12 – December 26 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| December 26 – January 9 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| January 23 – February 6 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| February 20 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by September 10 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 19 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| December 3 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 78757 is 3 miles from Austin-Camp Mabry, TX, which stands at 670 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 12 other ZIP codes share the station; its figures are presented in full for 78723 (Austin). The 2023 USDA Plant Hardiness Zone Map lists ZIP 78757 in zone 9a, the band where the coldest night of the year averaged 20 to 25°F (-6.7 to -3.9°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.