SmogRank / Spain / Basque Country / Tolosa

Tolosa, month by month

Tolosa has a measured daily mean on 272 days since 1 February 2024. Its worst month was August 2025, at 52 US AQI (9.8 µg/m³), 1,278th of 2,901 cities on that month's world ranking. Its cleanest was November 2025, at 28 US AQI (5.0 µg/m³).

Every month since 2024

2026too few days for a mean (a year needs 200)100 days measured
Jan18 daysFeb7 daysMarnoneAprnoneMaynoneJun5 daysJul17 daysAug44#1,619Sep45#971Oct5 days
2025too few days for a mean (a year needs 256)171 days measured
JannoneFebnoneMarnoneAprnoneMaynoneJun10 daysJul46#1,729Aug52#1,278Sep33#2,096Oct41#1,050Nov28#2,409Dec49#1,589
2024too few days for a mean (a year needs 257)1 day measured
JanFeb1 dayMarnoneAprnoneMaynoneJunnoneJulnoneAugnoneSepnoneOctnoneNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Tolosa'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 Tolosa 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

25 months
MonthWhy
Oct 20265 of 12 days measured; a month needs 9. The others: 1 with no readings from the monitors, 5 with readings for part of the day (a day needs 18 hours), 1 with under 18 hours of readings or readings that failed our checks.
Jul 202617 of 31 days measured; a month needs 22. The others: 14 with under 18 hours of readings or readings that failed our checks.
Jun 20265 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks.
May 2026No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Apr 2026No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Mar 2026No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Feb 20267 of 28 days measured; a month needs 20. The others: 21 with under 18 hours of readings or readings that failed our checks.
Jan 202618 of 31 days measured; a month needs 22. The others: 13 with under 18 hours of readings or readings that failed our checks.
Jun 202510 of 30 days measured; a month needs 21. The others: 20 with under 18 hours of readings or readings that failed our checks.
May 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Apr 2025No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Mar 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Feb 2025No day measured. The others: 28 with under 18 hours of readings or readings that failed our checks.
Jan 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Dec 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jul 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jun 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
May 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Apr 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Mar 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Feb 20241 of 29 days measured; a month needs 21. The others: 28 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.

Tolosa's worst months

MonthUS AQIDays measuredWorld rank
August 2025 529.8 µg/m³27 of 311,278thof 2,901
December 2025 498.9 µg/m³29 of 311,589thof 3,006
July 2025 468.2 µg/m³31 of 311,729thof 2,889
September 2026 458.1 µg/m³25 of 30971stof 2,981
August 2026 448.0 µg/m³23 of 311,619thof 2,896
October 2025 417.4 µg/m³22 of 311,050thof 2,614

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.

Tolosa's worst days

DayUS AQIEpisode
1 Feb 2024 8929.7 µg/m³Spain, Portugal and France, February 2024
12 Aug 2025 7320.7 µg/m³–
24 Jun 2025 7019.5 µg/m³–
11 Aug 2025 7019.3 µg/m³–
13 Aug 2025 6919.0 µg/m³–
13 Dec 2025 6918.9 µg/m³–
14 Aug 2025 6918.7 µg/m³–
13 Jul 2026 6717.8 µg/m³–
25 Jun 2026 6717.6 µg/m³–
12 Dec 2025 6215.2 µg/m³–

Daily means, the highest since 1 Feb 2024; 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, Tolosa, Spain, 1 Feb 2024 – 9 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/es/tolosa/history (accessed 12 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.

Tolosa 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).