Port Isabel, TX frost dates
Frost is light and occasional here — typically a few cold nights around midwinter (about 1 a year). Cover tender plants when frost is forecast.
How Port Isabel compares
- In a typical year, frost nights in Port Isabel fall between January 1 and January 3. In 1 year in 10 the first frost comes as early as December 7, or the last frost as late as February 2.
- Compared with Brownsville, TX, 22 km away, the last frost here is 6 days earlier than there.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | December 11 |
| 50% (median) | January 3 |
| 10% (safe for tender plants) | February 2 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | December 7 |
| 50% (median) | January 1 |
| 90% (late) | February 1 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Gardening where frost is rare
Port Isabel, TX only freezes on a few winter nights, so the usual "plant after the last frost" rule doesn't apply. Heat and rainfall decide the seasons instead:
- Cool-season crops (lettuce, broccoli, peas, carrots) grow best from fall through late winter.
- Warm-season crops (tomatoes, peppers, beans, squash) do best planted in late winter to spring, and again in late summer for a fall crop — midsummer heat can stop tomatoes setting fruit.
- Heat lovers (okra, sweet potatoes, melons) can be planted through spring and early summer.
About these dates
Based on 1991–2020 NOAA climate normals for the Port Isabel, TX weather station, 4 km away (elevation 16 ft (5 m)).
Frost dates near Port Isabel
- Los Fresnos Jan 8 · Jan 4
- Brownsville Jan 9 · Jan 4
- South Padre Island Jan 8 · Jan 4
- Olmito Jan 9 · Jan 4
- Lozano Jan 8 · Dec 29
- Rio Hondo Jan 8 · Dec 29
- San Benito Jan 9 · Jan 3
- Los Indios Jan 9 · Jan 3
- Harlingen Jan 9 · Jan 3
- Combes Jan 9 · Jan 3
Frequently asked questions
When is the last frost in Port Isabel, TX?
The median last spring frost in Port Isabel, TX is January 3. There is still about a 10% chance of frost after February 2, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Port Isabel, TX?
The median first fall frost is January 1, with about a 10% chance of frost before December 7.
How long is the growing season in Port Isabel, TX?
About 363 days between the median last spring frost and first fall frost.
What planting zone is Port Isabel, TX?
Port Isabel, TX is in USDA hardiness zone 10a.