USDA Hardiness Zone 9a
Frost Dates for 77423 — Brookshire, Texas
NOAA 1991–2020 normals from Sealy, TX (196 ft), 10 miles west.
Updated
In Brookshire, the last spring frost (32°F) is around February 28 in half of years and has passed by March 21 in nine years out of ten. The first fall frost comes around November 30, as early as November 9 one year in ten, leaving a typical freeze-free season of 276 days (NOAA, Sealy, TX).
- Last spring frost
- February 28
- First fall frost
- November 30
- Growing season
- 276 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
- 0%
- Snow per year
- 0"
median, 1991–2020
median, 1991–2020
0 of 17 observed
NOAA normal
Frost risk by date in Brookshire
Half of springs at Sealy, TX see their last 32°F night by February 28; only one in ten is past it by January 30, and one in ten still has one after March 21. Planting tender crops after March 8 leaves a 30% risk of a frost on them, after March 12 20%, and after March 21 10%. The 21 days between the even-odds date and the one-in-ten date is wider than at 50% 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 November 30 in half of years, as early as November 9 one year in ten, and holds off past December 29 one year in ten. A hard freeze of 28°F follows 20 days later, around December 20; in spring the one-in-ten date for 28°F is March 9, 12 days before the 32°F one. The freeze-free season lasts 276 days in a typical year, longer than at 76% of the 339 Texas stations; it reaches 311 days one year in ten and falls short of 245 one year in ten. On average 13 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 13 days longer, to about March 13, and return around November 17. Nights of 24°F, cold enough to damage hardier plants, come in 62% of winters and 16°F in 3%.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Feb 20 | Feb 27 | Mar 3 | Mar 8 | Mar 13 | Mar 17 | Mar 23 | Mar 31 | Apr 5 |
| 32°F | Jan 30 | Feb 9 | Feb 17 | Feb 23 | Feb 28 | Mar 3 | Mar 8 | Mar 12 | Mar 21 |
| 28°F94% of yrs | Jan 2 | Jan 19 | Jan 28 | Feb 3 | Feb 10 | Feb 18 | Feb 25 | Mar 2 | Mar 9 |
| 24°F62% of yrs | Dec 22 | Jan 1 | Jan 10 | Jan 22 | Jan 28 | Feb 1 | Feb 9 | Feb 21 | Mar 1 |
| 20°F20% of yrs | too rare for a date | ||||||||
| 16°F3% of yrs | too rare for a date | ||||||||
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Nov 1 | Nov 5 | Nov 9 | Nov 13 | Nov 17 | Nov 20 | Nov 25 | Dec 1 | Dec 6 |
| 32°F | Nov 9 | Nov 16 | Nov 20 | Nov 25 | Nov 30 | Dec 4 | Dec 8 | Dec 17 | Dec 29 |
| 28°F94% of yrs | Nov 20 | Nov 29 | Dec 4 | Dec 12 | Dec 20 | Dec 27 | Jan 2 | Jan 11 | Jan 29 |
| 24°F62% of yrs | Dec 4 | Dec 15 | Dec 25 | Jan 1 | Jan 5 | Jan 12 | Jan 21 | Feb 1 | Feb 10 |
| 20°F20% of yrs | too rare for a date | ||||||||
| 16°F3% of yrs | too rare for a date | ||||||||
Freeze probabilities 1991–2020 at Sealy, 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 77423 →Compare Brookshire with another place →
Weather by month in Brookshire
July is the warmest month at Sealy, TX, averaging 95°F by day and 74°F at night; January is the coldest at 64°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 77% of years and March still brings one in 46% of years.
Warmth for growing adds up to 7,318 growing degree days a year (base 50°F), more than at 75% of the 351 Texas stations. 42% of them (3,110) have built up by the end of June, and July adds the most, 1,062.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 64 | 42 | 89% | 5 | 167 |
| Feb | 68 | 45 | 77% | 2 | 213 |
| Mar | 74 | 52 | 46% | 1 | 400 |
| Apr | 79 | 58 | 4% | 0 | 556 |
| May | 86 | 66 | 0% | 0 | 811 |
| Jun | 92 | 72 | 0% | 0 | 964 |
| Jul | 95 | 74 | 0% | 0 | 1062 |
| Aug | 95 | 73 | 0% | 0 | 1055 |
| Sep | 90 | 69 | 0% | 0 | 889 |
| Oct | 82 | 59 | 1% | <1 | 647 |
| Nov | 73 | 50 | 50% | 2 | 355 |
| Dec | 66 | 44 | 82% | 4 | 202 |
Monthly normals 1991–2020 at Sealy, TX (196 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, Bellville 6NNE, TX, 21 miles northwest of Brookshire, has the same 50% last-frost date, a first frost 2 days later (December 2), a season 3 days longer.
When it snows in Brookshire, Texas
Measurable snow is rare here: only 0 of 17 winters from 1991 to 2020 recorded 0.1 inch or more at Katy City, TX, 9.9 miles away, so there is no typical first-snow date to plan around.
Planting calendar for 77423
| When | What to do |
|---|---|
| December 20 – January 3 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| January 3 – January 17 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| January 31 – February 14 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| February 28 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by September 7 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by November 16 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 30 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 77423 is 10 miles from Sealy, TX, which stands at 196 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 77441 (Fulshear). The 2023 USDA Plant Hardiness Zone Map lists ZIP 77423 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.