SmogRank / India / Tamil Nadu / Neelankarai

Neelankarai, month by month

Neelankarai has a measured daily mean on 509 days since 20 February 2025. Its worst month was December 2025, at 169 US AQI (80.6 µg/m³), 79th of 3,006 cities on that month's world ranking. Its cleanest was August 2026, at 58 US AQI (12.7 µg/m³).

Every month since 2025

202688 so far228 days measured202nd of 2,798 in the world
Jan21 daysFeb119#142Mar82#410Apr80#312May76#244Jun74#230Jul93#118Aug58#504Sep13 daysOctnone
202599 for the year281 days measured123rd of 2,681 in the world
JanFeb9 daysMar84#376Apr85#202May82#189Jun75#197Jul72#194Aug79#136Sep73#193Oct88#200Nov168#72Dec169#79
Each square is a month's mean PM2.5 in US AQI from Neelankarai'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 Neelankarai marked; each year, the year's.
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

4 months
MonthWhy
Oct 2026No day measured. The others: 12 with no readings from the monitor.
Sep 202613 of 30 days measured; a month needs 21. The others: 13 with no readings from the monitor, 4 with readings for part of the day (a day needs 18 hours).
Jan 202621 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Feb 20259 of 28 days measured; a month needs 20.

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

Neelankarai's worst months

MonthUS AQIDays measuredWorld rankEpisode
December 2025 16980.6 µg/m³27 of 3179thof 3,006–
November 2025 16879.3 µg/m³24 of 3072ndof 2,715Southern India, November 2025
February 2026 11942.8 µg/m³21 of 28142ndof 2,866–
July 2026 9331.7 µg/m³29 of 31118thof 2,784–
October 2025 8829.2 µg/m³23 of 31200thof 2,614Southern India, 12 to 14 October 2025
April 2025 8527.2 µg/m³24 of 30202ndof 2,951–

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.

Neelankarai's worst days

DayUS AQIEpisode
28 Nov 2025 500+454.0 µg/m³–
16 Nov 2025 443297.0 µg/m³–
13 Dec 2025 308229.0 µg/m³–
27 Nov 2025 244169.0 µg/m³–
13 Jul 2026 242167.0 µg/m³–
5 Sept 2026 237162.0 µg/m³–
12 Jul 2026 208133.0 µg/m³–
14 Nov 2025 196119.0 µg/m³Southern India, November 2025
30 Dec 2025 188108.0 µg/m³–
20 Dec 2025 187107.0 µg/m³–

Daily means, the highest since 20 Feb 2025; 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, Neelankarai, India, 20 Feb 2025 – 28 Sep 2026. Monitor data from CPCB via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/in/neelankarai/history (accessed 13 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.

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

Updated 2026-10-13 01:07 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).