SmogRank / Ireland / Connacht / Galway

Galway, month by month

Galway has a measured daily mean on 279 days since 22 May 2025. Its worst month was August 2025, at 42 US AQI (7.6 µg/m³), 1,940th of 2,901 cities on that month's world ranking. Its cleanest was July 2026, at 28 US AQI (5.1 µg/m³).

Every month since 2025

2026too few days for a mean (a year needs 200)175 days measured
Jan4 daysFeb1 dayMar3 daysApr37#2,009May31#2,118Jun17 daysJul28#2,581Aug29#2,710Sep35#1,593Oct29#1,901
2025too few days for a mean (a year needs 256)104 days measured
JanFebMarAprMay10 daysJun11 daysJul21 daysAug42#1,940Sep29#2,453Oct11 daysNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Galway'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 Galway 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

10 months
MonthWhy
Jun 202617 of 30 days measured; a month needs 21. The others: 13 with under 18 hours of readings or readings that failed our checks.
Mar 20263 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Feb 20261 of 28 days measured; a month needs 20. The others: 27 with under 18 hours of readings or readings that failed our checks.
Jan 20264 of 31 days measured; a month needs 22. The others: 27 with under 18 hours of readings or readings that failed our checks.
Dec 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2025No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 202511 of 31 days measured; a month needs 22. The others: 20 with under 18 hours of readings or readings that failed our checks.
Jul 202521 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Jun 202511 of 30 days measured; a month needs 21. The others: 19 with under 18 hours of readings or readings that failed our checks.
May 202510 of 31 days measured; a month needs 22.

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

Galway's worst months

MonthUS AQIDays measuredWorld rank
August 2025 427.6 µg/m³30 of 311,940thof 2,901
April 2026 376.6 µg/m³29 of 302,009thof 2,941
September 2026 356.3 µg/m³26 of 301,593rdof 2,997
May 2026 315.6 µg/m³29 of 312,118thof 2,874
September 2025 295.3 µg/m³21 of 302,453rdof 3,104
August 2026 295.2 µg/m³27 of 312,710thof 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.

Galway's worst days

DayUS AQI
24 Jul 2025 6918.8 µg/m³
11 Sept 2026 6918.5 µg/m³
12 Aug 2025 6516.7 µg/m³
27 Aug 2026 6416.1 µg/m³
30 Mar 2026 6014.0 µg/m³
28 Aug 2026 5913.5 µg/m³
29 Mar 2026 5913.2 µg/m³
15 Aug 2025 5813.0 µg/m³
15 Jul 2026 5712.5 µg/m³
17 Jul 2026 5511.2 µg/m³

Daily means, the highest since 22 May 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, Galway, Ireland, 22 May 2025 – 12 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/ie/galway/history (accessed 13 Oct 2026).

Download chart (PNG)

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.

Galway 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).