SmogRank / Puerto Rico / Cataño / Cataño

Cataño, month by month

Cataño has a measured daily mean on 726 days since 6 July 2023. Its worst month was July 2026, at 61 US AQI (14.5 µg/m³), 551st of 2,784 cities on that month's world ranking. Its cleanest was November 2025, at 32 US AQI (5.7 µg/m³).

Every month since 2023

2026too few days for a mean (a year needs 199)198 days measured
Jan33#2,149FebnoneMar18 daysApr36#2,046May41#1,539Jun13 daysJul61#551Aug58#500Sep54#606Oct37#1,498
202552 for the year338 days measured1,186th of 2,681 in the world
Jan40#1,640Feb42#1,705Mar45#1,915Apr47#1,655May49#1,142Jun59#627Jul60#509Aug59#542Sep55#514Oct40#1,105Nov32#2,247Dec21 days
2024too few days for a mean (a year needs 257)162 days measured
JannoneFebnoneMarnoneAprnoneMay17 daysJun52#788Jul58#312Aug19 daysSep37#1,259Oct14 daysNov5 daysDec44#1,364
2023too few days for a mean (a year needs 256)28 days measured
JanFebMarAprMayJunJul15 daysAug13 daysSepnoneOctnoneNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Cataño's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Cataño marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

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

18 months
MonthWhy
Jun 202613 of 30 days measured; a month needs 21. The others: 17 with under 18 hours of readings or readings that failed our checks.
Mar 202618 of 31 days measured; a month needs 22. The others: 13 with under 18 hours of readings or readings that failed our checks.
Feb 2026No day measured. The others: 28 with under 18 hours of readings or readings that failed our checks.
Dec 202521 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Nov 20245 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks.
Oct 202414 of 31 days measured; a month needs 22. The others: 17 with under 18 hours of readings or readings that failed our checks.
Aug 202419 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
May 202417 of 31 days measured; a month needs 22. The others: 14 with under 18 hours of readings or readings that failed our checks.
Apr 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Mar 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Feb 2024No day measured. The others: 1 missing from OpenAQ's archive, 28 with under 18 hours of readings or readings that failed our checks.
Jan 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Dec 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 202313 of 31 days measured; a month needs 22. The others: 18 with under 18 hours of readings or readings that failed our checks.
Jul 202315 of 31 days measured; a month needs 22. The others: 1 missing from OpenAQ's archive, 10 with under 18 hours of readings or readings that failed our checks.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Cataño's worst months

MonthUS AQIDays measuredWorld rank
July 2026 6114.5 µg/m³26 of 31551stof 2,784
July 2025 6014.0 µg/m³31 of 31509thof 2,889
June 2025 5913.3 µg/m³28 of 30627thof 2,508
August 2025 5913.2 µg/m³31 of 31542ndof 2,901
July 2024 5812.9 µg/m³27 of 31312thof 2,566
August 2026 5812.8 µg/m³31 of 31500thof 2,896

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.

Cataño's worst days

DayUS AQI
20 May 2024 15866.0 µg/m³
19 May 2024 15764.4 µg/m³
16 May 2024 15763.8 µg/m³
14 May 2024 15561.6 µg/m³
12 May 2024 15560.7 µg/m³
17 May 2024 15459.9 µg/m³
13 May 2024 15358.9 µg/m³
18 May 2024 15357.8 µg/m³
11 May 2024 15156.2 µg/m³
15 May 2024 13750.3 µg/m³

Daily means, the highest since 6 Jul 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, Cataño, Puerto Rico, 6 Jul 2023 – 8 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/pr/catano/history (accessed 12 Oct 2026).

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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.

Cataño now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 18:07 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).