SmogRank / India / Kerala / Thrissur

Thrissur, month by month

Thrissur has a measured daily mean on 446 days since 19 February 2025. Its worst month was May 2025, at 92 US AQI (31.1 µg/m³), 136th of 2,826 cities on that month's world ranking. Its cleanest was July 2025, at 79 US AQI (24.1 µg/m³).

Every month since 2025

2026too few days for a mean (a year needs 200)192 days measured
Jan14 daysFeb17 daysMar87#317Apr89#241May84#205Jun20 daysJul81#210Aug19 daysSep92#118Oct3 days
2025too few days for a mean (a year needs 256)254 days measured
JanFeb9 daysMar91#278Apr18 daysMay92#136Jun79#176Jul79#147Aug84#106Sep90#79Oct88#201Nov19 daysDec91#304
Each square is a month's mean PM2.5 in US AQI from Thrissur'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 Thrissur 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

8 months
MonthWhy
Oct 20263 of 12 days measured; a month needs 9. The others: 5 with no readings from the monitor, 4 with readings for part of the day (a day needs 18 hours).
Aug 202619 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Jun 202620 of 30 days measured; a month needs 21. The others: 10 with under 18 hours of readings or readings that failed our checks.
Feb 202617 of 28 days measured; a month needs 20. The others: 11 with under 18 hours of readings or readings that failed our checks.
Jan 202614 of 31 days measured; a month needs 22. The others: 17 with under 18 hours of readings or readings that failed our checks.
Nov 202519 of 30 days measured; a month needs 21. The others: 11 with under 18 hours of readings or readings that failed our checks.
Apr 202518 of 30 days measured; a month needs 21. The others: 12 with under 18 hours of readings or readings that failed our checks.
Feb 20259 of 28 days measured; a month needs 20. The others: 1 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.

Thrissur's worst months

MonthUS AQIDays measuredWorld rank
May 2025 9231.1 µg/m³23 of 31136thof 2,826
September 2026 9230.9 µg/m³24 of 30118thof 2,997
December 2025 9130.7 µg/m³28 of 31304thof 3,006
March 2025 9130.5 µg/m³24 of 31278thof 2,862
September 2025 9030.3 µg/m³27 of 3079thof 3,104
April 2026 8929.3 µg/m³24 of 30241stof 2,941

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.

Thrissur's worst days

DayUS AQI
31 Jan 2026 14754.1 µg/m³
25 Jan 2026 14151.8 µg/m³
23 Jan 2026 13850.6 µg/m³
30 Jan 2026 13549.3 µg/m³
22 Jan 2026 13348.5 µg/m³
6 Feb 2026 13047.1 µg/m³
10 Feb 2026 12846.5 µg/m³
9 Feb 2026 12244.0 µg/m³
11 Feb 2026 11942.8 µg/m³
7 Feb 2026 11942.7 µg/m³

Daily means, the highest since 19 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, Thrissur, India, 19 Feb 2025 – 6 Oct 2026. Monitor data from CPCB via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/in/thrissur/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.

Thrissur 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).