SmogRank / United States / Texas / Port Isabel
Port Isabel, month by month
Port Isabel has a measured daily mean on 1,204 days since 1 January 2023. Its worst month was May 2024, at 135 US AQI (49.4 µg/m³), 31st of 2,684 cities on that month's world ranking. Its cleanest was September 2023, at 30 US AQI (5.4 µg/m³). 2025 averaged 59 US AQI (13.4 µg/m³), against 74 US AQI (21.4 µg/m³) in 2024.
Every month since 2023
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
Months without a mean, and why
6 months
| Month | Why |
|---|---|
| Oct 2026 | 2 of 11 days measured; a month needs 8. The others: 7 with no readings from the monitor, 2 with readings for part of the day (a day needs 18 hours). |
| Nov 2025 | 15 of 30 days measured; a month needs 21. The others: 4 with no readings from the monitor, 11 with readings for part of the day (a day needs 18 hours). |
| Jul 2025 | 20 of 31 days measured; a month needs 22. The others: 3 with no readings from the monitor, 4 with readings for part of the day (a day needs 18 hours), 4 with readings left out by our checks. |
| Feb 2024 | 20 of 29 days measured; a month needs 21. The others: 6 with no readings from the monitor, 2 with readings for part of the day (a day needs 18 hours), 1 missing from OpenAQ's archive. |
| Mar 2023 | 10 of 31 days measured; a month needs 22. The others: 1 with readings for part of the day (a day needs 18 hours), 20 missing from OpenAQ's archive. |
| Feb 2023 | 2 of 28 days measured; a month needs 20. The others: 1 with readings for part of the day (a day needs 18 hours), 25 missing from OpenAQ's archive. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Port Isabel's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| May 2024 | 13549.4 µg/m³ | 31stof 2,684 | Southern United States and Mexico, 19 to 28 May 2024 Southern United States and Mexico, 15 to 16 May 2024and 1 more |
| April 2024 | 10336.2 µg/m³ | 56thof 2,520 | Texas, United States, April 2024 Southern United States and Mexico, April 2024 |
| March 2024 | 8225.5 µg/m³ | 67thof 1,698 | Southern United States and Mexico, March 2024 |
| June 2024 | 7823.5 µg/m³ | 71stof 2,563 | Southern United States and Mexico, June 2024 |
| January 2024 | 7320.9 µg/m³ | 248thof 2,385 | – |
| May 2025 | 6717.8 µg/m³ | 323rdof 2,826 | – |
Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.
Port Isabel's worst days
| Day | US AQI | Episode |
|---|---|---|
| 10 May 2024 | 17285.7 µg/m³ | Southern United States and Mexico, 7 to 10 May 2024 |
| 17 May 2024 | 17082.0 µg/m³ | – |
| 9 May 2024 | 16677.6 µg/m³ | Southern United States and Mexico, 7 to 10 May 2024 |
| 27 May 2024 | 16575.1 µg/m³ | Southern United States and Mexico, 19 to 28 May 2024 |
| 16 May 2024 | 16069.0 µg/m³ | Southern United States and Mexico, 15 to 16 May 2024 |
| 26 May 2024 | 15866.1 µg/m³ | Southern United States and Mexico, 19 to 28 May 2024 |
| 8 May 2024 | 15865.5 µg/m³ | Southern United States and Mexico, 7 to 10 May 2024 |
| 5 Jun 2024 | 15864.8 µg/m³ | Southern United States and Mexico, June 2024 |
| 29 Apr 2024 | 15764.2 µg/m³ | – |
| 23 Jan 2024 | 15560.8 µg/m³ | – |
Daily means, the highest since 1 Jan 2023; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.
Use this history
SmogRank, PM2.5 monthly and daily means, Port Isabel, United States, 1 Jan 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/port-isabel/history (accessed 13 Oct 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.
Port Isabel now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-13 00:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).