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Will it freeze in Port Isabel in the next 7 nights?
No overnight lows at or below 32°F are forecast in Port Isabel during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 72°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 72°F Above 36°F · Chance Showers And Thunderstorms
- Fri, Nov 6 70°F Above 36°F · Chance Rain Showers
- Sat, Nov 7 68°F Above 36°F · Showers And Thunderstorms
- Sun, Nov 8 63°F Above 36°F · Showers And Thunderstorms Likely
- Mon, Nov 9 63°F Above 36°F · Chance Rain Showers
- Tue, Nov 10 64°F Above 36°F · Mostly Cloudy
- Wed, Nov 11 65°F Above 36°F · Mostly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Port Isabel
Most years have no 28°F hard freeze at Port Isabel, according to NOAA’s 1991–2020 Climate Normals. Check the short-term forecast above during cold snaps.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Dec 18 · Jan 17 · Feb 24 | Dec 1 · Dec 25 · Jan 31 | 347 days |
| 32°F freeze | Dec 11 · Jan 3 · Feb 2 | Dec 7 · Jan 1 · Feb 1 | 365 days |
| 28°F hard freeze | Dec 12 · Jan 2 · Jan 22 | Dec 12 · Jan 1 · Jan 20 | 365 days |
Average high temperature by month
1991–2020 normals at Port Isabel
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Port Isabel, TX come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Port Isabel (station USC00417179, elevation 17 ft), 2.0 mi from Port Isabel. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Port Isabel
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Los Fresnos, TX | 11 mi | rare | rare |
| Brownsville, TX | 12 mi | rare | rare |
| San Benito, TX | 21 mi | rare | rare |
| Harlingen, TX | 25 mi | rare | rare |
| Primera, TX | 29 mi | rare | rare |
| La Feria, TX | 32 mi | Jan 10 | Dec 27 |
| Mercedes, TX | 38 mi | rare | rare |
| Progreso, TX | 40 mi | rare | rare |
| Raymondville, TX | 40 mi | Jan 21 | Dec 26 |
| Weslaco, TX | 42 mi | rare | rare |
Frequently asked questions
When is the last frost in Port Isabel?
Port Isabel doesn’t reach 32°F in a typical year, according to NOAA’s 1991–2020 normals for the nearest station.
When is the first frost in Port Isabel?
Freezes are uncommon here; check the 7-night forecast above during cold snaps.
Can it frost in Port Isabel after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after January 17.
What growing zone is Port Isabel?
Port Isabel is in USDA Plant Hardiness Zone 10a (average annual extreme minimum temperature 30 to 35°F), based on the 2023 USDA map for ZIP code 78578. See growing zones in Texas.
More: all Texas frost dates · Texas growing zones · frost vs. freeze