Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 78373 — Port Aransas, TX

ZIP code 78373 (Port Aransas, Nueces County) is in USDA zone 10a: the coldest winter night averages 30 to 35 °F.

Where ZIP 78373 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone10a30 to 35 °F
Coldest night−1.1 to 1.7 °C
Last frostrare
First frostrare
2012 zone10a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 10a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Port Aransas, TX…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Port Aransas 11 Ssw, TX — 6 miles away, elevation 7 ft) the median growing season is 362 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 78373 came on Jan 10 — 9 days earlier than the 1991–2020 average (Jan 19).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 10a in Texas

651 plants native to the lower 48 states, recorded in Texas, and rated by the USDA to survive 30 °F or colder — the bottom of zone 10a. Each links to its USDA PLANTS profile.

Trees 72

Shrubs 147

Wildflowers & perennials 212

Grasses 197

Vines 14

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Port Aransas, TX.

Soil in Port Aransas, TX

The center of ZIP 78373 is mapped as Tidal flats, occasionally ponded: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 78373; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Port Aransas, TX

Summer high91 °Faverage high, August
Winter low49 °Faverage low, January
Hot days54days a year at 90 °F or more
Freezing nights1nights a year at 32 °F or less
Growing degree days8,075base 50 °F — the season’s usable heat
Longest day13 h 54 mindaylight on June 21
Shortest day10 h 23 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation34.1 inper year, rain and melted snow

Average high and low, by month

40°50°60°70°80°90°100°January: average high 63 °F, low 49 °F 63°49° JanFebruary: average high 66 °F, low 52 °F 66°52° FebMarch: average high 71 °F, low 57 °F 71°57° MarApril: average high 77 °F, low 65 °F 77°65° AprMay: average high 83 °F, low 72 °F 83°72° MayJune: average high 89 °F, low 77 °F 89°77° JunJuly: average high 89 °F, low 79 °F 89°79° JulAugust: average high 91 °F, low 79 °F 91°79° AugSeptember: average high 89 °F, low 75 °F 89°75° SepOctober: average high 83 °F, low 70 °F 83°70° OctNovember: average high 73 °F, low 60 °F 73°60° NovDecember: average high 67 °F, low 52 °F 67°52° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 1.96 in precipitation 2.0 JanFebruary: 1.56 in precipitation 1.6 FebMarch: 2.15 in precipitation 2.1 MarApril: 2.07 in precipitation 2.1 AprMay: 4.41 in precipitation 4.4 MayJune: 3.82 in precipitation 3.8 JunJuly: 2.81 in precipitation 2.8 JulAugust: 1.91 in precipitation 1.9 AugSeptember: 5.45 in precipitation 5.5 SepOctober: 3.62 in precipitation 3.6 OctNovember: 2.44 in precipitation 2.4 NovDecember: 1.88 in precipitation 1.9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Port Aransas 11 Ssw, TX (6 mi away); precipitation: Port Aransas 11 Ssw, TX (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

1 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

Texas planting zones →

Questions about 78373

What planting zone is ZIP code 78373?

ZIP code 78373 (Port Aransas, TX) is in USDA hardiness zone 10a on the 2023 map: the coldest night of an average winter reaches 30 to 35 °F (−1.1 to 1.7 °C).

How much rain and snow does 78373 get?

About 34.1 inches of precipitation a year (NOAA 1991–2020 normals, Port Aransas 11 Ssw station).

How hot do summers get in Port Aransas, TX?

The average high peaks at 91 °F in August, with about 54 days a year at 90 °F or more.

Did spring come early in Port Aransas, TX in 2026?

Spring leaf-out near 78373 came on Jan 10 in 2026, 9 days earlier than the 1991–2020 average (Jan 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Port Aransas, TX?

Short-day onions: the longest day near 78373 is 13 h 54 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.