SmogRank / Portugal / Madeira / Santana
Santana, month by month
Santana, Madeira has a measured daily mean on 891 days since 1 January 2023. Its worst month was December 2024, at 54 US AQI (10.7 µg/m³), 790th of 2,616 cities on that month's world ranking. Its cleanest was April 2025, at 7 US AQI (1.3 µg/m³). 2025 averaged 14 US AQI (2.6 µg/m³), against 17 US AQI (3.0 µg/m³) in 2023.
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
18 months
| Month | Why |
|---|---|
| Aug 2026 | 18 of 31 days measured; a month needs 22. The others: 9 with no readings from the monitor, 4 with readings for part of the day (a day needs 18 hours). |
| Jul 2026 | No day measured. The others: 31 with no readings from the monitor. |
| Jun 2026 | No day measured. The others: 30 with no readings from the monitor. |
| May 2026 | No day measured. The others: 31 with no readings from the monitor. |
| Apr 2026 | No day measured. The others: 30 with no readings from the monitor. |
| Mar 2026 | No day measured. The others: 31 with no readings from the monitor. |
| Feb 2026 | 11 of 28 days measured; a month needs 20. The others: 12 with no readings from the monitor, 5 with readings for part of the day (a day needs 18 hours). |
| Jan 2026 | 20 of 31 days measured; a month needs 22. The others: 11 with readings for part of the day (a day needs 18 hours). |
| Oct 2025 | 18 of 31 days measured; a month needs 22. The others: 13 with readings for part of the day (a day needs 18 hours). |
| Jun 2025 | 19 of 30 days measured; a month needs 21. The others: 11 with readings for part of the day (a day needs 18 hours). |
| May 2025 | 19 of 31 days measured; a month needs 22. The others: 1 with no readings from the monitor, 11 with readings for part of the day (a day needs 18 hours). |
| Oct 2024 | 13 of 31 days measured; a month needs 22. The others: 17 with readings for part of the day (a day needs 18 hours), 1 with readings left out by our checks. |
| Sep 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). |
| Aug 2024 | 15 of 31 days measured; a month needs 22. The others: 3 with no readings from the monitor, 13 with readings for part of the day (a day needs 18 hours). |
| May 2024 | 18 of 31 days measured; a month needs 22. The others: 7 with no readings from the monitor, 6 with readings for part of the day (a day needs 18 hours). |
| Mar 2024 | 14 of 31 days measured; a month needs 22. The others: 10 with no readings from the monitor, 7 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. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Santana's worst months
| Month | US AQI | World rank |
|---|---|---|
| December 2024 | 5410.7 µg/m³ | 790thof 2,616 |
| September 2026 | 366.4 µg/m³ | 1,535thof 2,981 |
| October 2023 | 336.0 µg/m³ | 1,492ndof 2,012 |
| August 2025 | 285.0 µg/m³ | 2,697thof 2,901 |
| November 2024 | 264.7 µg/m³ | 2,357thof 2,624 |
| April 2024 | 223.9 µg/m³ | 2,259thof 2,520 |
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.
Santana's worst days
| Day | US AQI |
|---|---|
| 8 Dec 2024 | 12946.9 µg/m³ |
| 19 Dec 2024 | 11641.7 µg/m³ |
| 16 Dec 2024 | 11541.0 µg/m³ |
| 13 Dec 2024 | 11139.6 µg/m³ |
| 28 Jan 2024 | 8226.0 µg/m³ |
| 14 Oct 2023 | 7823.4 µg/m³ |
| 29 Jun 2023 | 7522.2 µg/m³ |
| 14 Feb 2023 | 7421.5 µg/m³ |
| 28 Nov 2024 | 7220.4 µg/m³ |
| 17 Dec 2024 | 7120.0 µg/m³ |
Daily means, the highest since 1 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, Santana, Madeira, Portugal, 1 Jan 2023 – 11 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/pt/santana/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.
Santana now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 20:07 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).