SmogRank / France / Normandy / Le Trait
Le Trait, month by month
Le Trait has a measured daily mean on 344 days since 17 January 2023. Its worst month was January 2024, at 61 US AQI (14.4 µg/m³), 511th of 2,385 cities on that month's world ranking. Its cleanest was August 2023, at 17 US AQI (3.1 µg/m³).
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
35 months
| Month | Why |
|---|---|
| Oct 2026 | 1 of 12 days measured; a month needs 9. The others: 4 with no readings from the monitor, 5 with readings for part of the day (a day needs 18 hours), 2 with under 18 hours of readings or readings that failed our checks. |
| Sep 2026 | 1 of 30 days measured; a month needs 21. The others: 29 with readings for part of the day (a day needs 18 hours). |
| Aug 2026 | No day measured. The others: 31 with readings for part of the day (a day needs 18 hours). |
| Jul 2026 | No day measured. The others: 2 with no readings from the monitor, 29 with readings for part of the day (a day needs 18 hours). |
| Jun 2026 | 1 of 30 days measured; a month needs 21. The others: 7 with no readings from the monitor, 22 with readings for part of the day (a day needs 18 hours). |
| May 2026 | 2 of 31 days measured; a month needs 22. The others: 1 with no readings from the monitor, 28 with readings for part of the day (a day needs 18 hours). |
| Apr 2026 | No day measured. The others: 30 with readings for part of the day (a day needs 18 hours). |
| Mar 2026 | No day measured. The others: 3 with no readings from the monitor, 28 with readings for part of the day (a day needs 18 hours). |
| Feb 2026 | No day measured. The others: 28 with readings for part of the day (a day needs 18 hours). |
| Jan 2026 | 3 of 31 days measured; a month needs 22. The others: 28 with readings for part of the day (a day needs 18 hours). |
| Dec 2025 | No day measured. |
| Nov 2025 | No day measured. |
| Oct 2025 | No day measured. |
| Sep 2025 | No day measured. |
| Aug 2025 | No day measured. |
| Jul 2025 | No day measured. |
| Jun 2025 | No day measured. |
| May 2025 | No day measured. |
| Apr 2025 | No day measured. |
| Mar 2025 | No day measured. |
| Feb 2025 | No day measured. |
| Jan 2025 | No day measured. |
| Dec 2024 | No day measured. The others: 31 with readings for part of the day (a day needs 18 hours). |
| Nov 2024 | No day measured. The others: 30 with readings for part of the day (a day needs 18 hours). |
| Oct 2024 | No day measured. The others: 31 with readings for part of the day (a day needs 18 hours). |
| Sep 2024 | No day measured. The others: 7 with no readings from the monitor, 23 with readings for part of the day (a day needs 18 hours). |
| Aug 2024 | 6 of 31 days measured; a month needs 22. The others: 1 with no readings from the monitor, 24 with readings for part of the day (a day needs 18 hours). |
| Jul 2024 | 4 of 31 days measured; a month needs 22. The others: 1 with no readings from the monitor, 26 with readings for part of the day (a day needs 18 hours). |
| Jun 2024 | No day measured. The others: 1 with no readings from the monitor, 29 with readings for part of the day (a day needs 18 hours). |
| May 2024 | No day measured. The others: 31 with readings for part of the day (a day needs 18 hours). |
| Apr 2024 | 2 of 30 days measured; a month needs 21. The others: 28 with readings for part of the day (a day needs 18 hours). |
| Mar 2024 | 10 of 31 days measured; a month needs 22. The others: 10 with no readings from the monitor, 11 with readings for part of the day (a day needs 18 hours). |
| Mar 2023 | 11 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive. |
| Feb 2023 | 3 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive. |
| Jan 2023 | 3 of 31 days measured; a month needs 22. The others: 11 with readings for part of the day (a day needs 18 hours), 1 missing from OpenAQ's archive. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Le Trait's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| January 2024 | 6114.4 µg/m³ | 511thof 2,385 | Europe, 8 to 27 January 2024 Western Europe, January 2024 |
| May 2023 | 5310.1 µg/m³ | 455thof 1,600 | – |
| December 2023 | 519.1 µg/m³ | 928thof 2,247 | France, Belgium and 2 more countries, November and December 2023 |
| April 2023 | 478.5 µg/m³ | 716thof 1,622 | France, Belgium and Germany, April 2023 |
| June 2023 | 478.5 µg/m³ | 1,026thof 1,603 | – |
| October 2023 | 478.5 µg/m³ | 620thof 2,012 | – |
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.
Le Trait's worst days
| Day | US AQI | Episode |
|---|---|---|
| 8 Oct 2023 | 16169.6 µg/m³ | – |
| 15 Feb 2023 | 10637.5 µg/m³ | Europe, 6 to 25 February 2023 |
| 19 Jan 2024 | 9934.9 µg/m³ | Europe, 8 to 27 January 2024 |
| 14 Feb 2023 | 8929.4 µg/m³ | Europe, 6 to 25 February 2023 |
| 2 Dec 2023 | 8426.7 µg/m³ | France, Belgium and 2 more countries, November and December 2023 |
| 18 Apr 2023 | 8225.6 µg/m³ | France, Belgium and Germany, April 2023 |
| 16 Jan 2024 | 8225.5 µg/m³ | Europe, 8 to 27 January 2024 Western Europe, January 2024 |
| 20 Jan 2024 | 8024.4 µg/m³ | Europe, 8 to 27 January 2024 |
| 10 Jan 2024 | 7723.2 µg/m³ | Europe, 8 to 27 January 2024 |
| 11 Jan 2024 | 7723.1 µg/m³ | Europe, 8 to 27 January 2024 |
Daily means, the highest since 17 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, Le Trait, France, 17 Jan 2023 – 7 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/fr/le-trait/history (accessed 12 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.
Le Trait now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 21:07 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).