SmogRank / Episodes / Spain

North-eastern Spain, September 2023

For 2 days, from 4 to 5 September 2023, 11 cities in Spain and France had PM2.5 at least twice their usual for the time of year. The worst reading was Coslada, Madrid, Spain: 107.0 µg/m³ on 4 September, about 13× its usual 8.3.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached11in 2 countries
Days24 to 5 September 2023
Worst day5 September9 cities counted
Furthest above usual13×Coslada

Day by day

5 September 9 cities at twice their usual or more
ValenciaOndaSaguntoAlcalá de HenaresGrao de MurviedroXàtivaTorrejón de ArdozBurrianaCastelló de la PlanaAlgeteBenicàssimValdemoroMadridMóstolesAlicanteToledoCalahorraCollado-VillalbaCiudad RealBailénBurgosJaénZarautzValladolidPalenciaMedina del CampoGranadaAngletBermeoPauTarbesCórdobaDaxSalamancales EscaldesMálagaCártamaPalmaLeónMarratxíToulouseSevillaSamaGijónOviedoPerpignanAvilésSan FernandoHuelvaAlgiersLaudio / LlodioBilbaoDurangoGasteiz / VitoriaDonostia / San SebastiánAlmeríaLourdesTorreviejaEldaCuencaCoslada
1 Sep2345678
Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.

How it spread

CosladaCoslada, 1 September: 11.2 µg/m³, 1.3× usualCoslada, 2 September: 41.9 µg/m³, 5.0× usualCoslada, 3 September: 42.4 µg/m³, 5.1× usualCoslada, 4 September: 107.0 µg/m³, 13× usualCoslada, 5 September: 19.1 µg/m³, 2.3× usualCoslada, 6 September: 15.8 µg/m³, 1.9× usualCoslada, 7 September: 16.0 µg/m³, 1.9× usualCoslada, 8 September: 12.9 µg/m³, 1.6× usualCuencaCuenca, 1 September: 11.1 µg/m³, 1.0× usualCuenca, 2 September: 7.2 µg/m³, 0.6× usualCuenca, 3 September: 11.7 µg/m³, 1.0× usualCuenca, 4 September: 100.0 µg/m³, 8.6× usualCuenca, 5 September: 42.4 µg/m³, 3.7× usualCuenca, 6 September: 22.9 µg/m³, 2.0× usualCuenca, 7 September: 16.8 µg/m³, 1.4× usualCuenca, 8 September: 14.2 µg/m³, 1.2× usualTorreviejaTorrevieja, 1 September: no readingTorrevieja, 2 September: 3.9 µg/m³, 0.5× usualTorrevieja, 3 September: 11.7 µg/m³, 1.5× usualTorrevieja, 4 September: 42.9 µg/m³, 5.6× usualTorrevieja, 5 September: 34.5 µg/m³, 4.5× usualTorrevieja, 6 September: 6.5 µg/m³, 0.9× usualTorrevieja, 7 September: 8.6 µg/m³, 1.1× usualTorrevieja, 8 September: 7.9 µg/m³, 1.0× usualEldaElda, 1 September: 3.6 µg/m³, 0.6× usualElda, 2 September: 2.9 µg/m³, 0.5× usualElda, 3 September: 7.3 µg/m³, 1.3× usualElda, 4 September: 37.2 µg/m³, 6.6× usualElda, 5 September: 15.5 µg/m³, 2.8× usualElda, 6 September: 5.6 µg/m³, 1.0× usualElda, 7 September: 4.7 µg/m³, 0.8× usualElda, 8 September: 5.9 µg/m³, 1.1× usualDurangoDurango, 1 September: 8.7 µg/m³, 1.1× usualDurango, 2 September: 3.6 µg/m³, 0.5× usualDurango, 3 September: 5.6 µg/m³, 0.7× usualDurango, 4 September: 18.5 µg/m³, 2.3× usualDurango, 5 September: 32.7 µg/m³, 4.1× usualDurango, 6 September: 17.6 µg/m³, 2.2× usualDurango, 7 September: 13.7 µg/m³, 1.7× usualDurango, 8 September: 13.4 µg/m³, 1.7× usualGasteiz / VitoriaGasteiz / Vitoria, 1 September: 11.3 µg/m³, 1.5× usualGasteiz / Vitoria, 2 September: 3.8 µg/m³, 0.5× usualGasteiz / Vitoria, 3 September: 5.8 µg/m³, 0.8× usualGasteiz / Vitoria, 4 September: 23.3 µg/m³, 3.1× usualGasteiz / Vitoria, 5 September: 32.6 µg/m³, 4.3× usualGasteiz / Vitoria, 6 September: 19.2 µg/m³, 2.5× usualGasteiz / Vitoria, 7 September: 14.6 µg/m³, 1.9× usualGasteiz / Vitoria, 8 September: 12.6 µg/m³, 1.7× usualAlmeríaAlmería, 1 September: no readingAlmería, 2 September: 4.6 µg/m³, 0.8× usualAlmería, 3 September: 14.0 µg/m³, 2.3× usualAlmería, 4 September: 15.8 µg/m³, 2.6× usualAlmería, 5 September: 29.9 µg/m³, 5.0× usualAlmería, 6 September: 20.6 µg/m³, 3.4× usualAlmería, 7 September: 6.2 µg/m³, 1.0× usualAlmería, 8 September: 6.7 µg/m³, 1.1× usualBilbaoBilbao, 1 September: no readingBilbao, 2 September: 5.1 µg/m³, 0.7× usualBilbao, 3 September: 6.6 µg/m³, 0.9× usualBilbao, 4 September: 17.5 µg/m³, 2.4× usualBilbao, 5 September: 27.9 µg/m³, 3.8× usualBilbao, 6 September: 21.0 µg/m³, 2.8× usualBilbao, 7 September: 14.6 µg/m³, 2.0× usualBilbao, 8 September: 14.6 µg/m³, 2.0× usualLourdesLourdes, 1 September: 3.8 µg/m³, 0.8× usualLourdes, 2 September: 2.2 µg/m³, 0.4× usualLourdes, 3 September: 5.0 µg/m³, 1.0× usualLourdes, 4 September: 16.0 µg/m³, 3.2× usualLourdes, 5 September: 27.8 µg/m³, 5.6× usualLourdes, 6 September: 18.9 µg/m³, 3.8× usualLourdes, 7 September: 12.5 µg/m³, 2.5× usualLourdes, 8 September: 12.2 µg/m³, 2.4× usualLaudio / LlodioLaudio / Llodio, 1 September: no readingLaudio / Llodio, 2 September: 5.5 µg/m³, 0.7× usualLaudio / Llodio, 3 September: 7.1 µg/m³, 1.0× usualLaudio / Llodio, 4 September: no readingLaudio / Llodio, 5 September: 27.7 µg/m³, 3.7× usualLaudio / Llodio, 6 September: 20.7 µg/m³, 2.8× usualLaudio / Llodio, 7 September: 14.3 µg/m³, 1.9× usualLaudio / Llodio, 8 September: 16.0 µg/m³, 2.2× usualDonostia / San Seba…Donostia / San Sebastián, 1 September: no readingDonostia / San Sebastián, 2 September: 3.1 µg/m³, 0.5× usualDonostia / San Sebastián, 3 September: 4.4 µg/m³, 0.7× usualDonostia / San Sebastián, 4 September: 11.0 µg/m³, 1.8× usualDonostia / San Sebastián, 5 September: 27.4 µg/m³, 4.4× usualDonostia / San Sebastián, 6 September: 11.3 µg/m³, 1.8× usualDonostia / San Sebastián, 7 September: 11.1 µg/m³, 1.8× usualDonostia / San Sebastián, 8 September: 16.4 µg/m³, 2.6× usual1 Sep2345678
Every counted city, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

Every city it reached

CityDaysHighestUsualAbove usual
CosladaMadrid, Spain1 107.04 September8.313×
CuencaCastille-La Mancha, Spain2 100.04 September11.68.6×
EldaValencia, Spain1 37.24 September5.66.6×
TorreviejaValencia, Spain2 42.94 September7.65.6×
LourdesOccitanie, France1 27.85 September4.95.6×
AlmeríaAndalusia, Spain1 29.95 September6.05.0×
Donostia / San SebastiánBasque Country, Spain1 27.45 September6.24.4×
Gasteiz / VitoriaBasque Country, Spain1 32.65 September7.64.3×
DurangoBasque Country, Spain1 32.75 September7.94.1×
BilbaoBasque Country, Spain1 27.95 September7.43.8×
Laudio / LlodioBasque Country, Spain1 27.75 September7.43.7×

Daily means in µg/m³. Usual: the city's median for this time of year (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that.

Against other episodes in Spain and France

Number 17 of 23 episodes in Spain and France since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 23.

Use this page

SmogRank, North-eastern Spain, September 2023: 11 cities with PM2.5 at twice their usual or more, 4 to 5 September 2023, smogrank.com/episodes/2023-09-north-eastern-spain (accessed 2 October 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms.

An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes. Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source.