SmogRank / Episodes / Brazil

Rio de Janeiro and São Paulo, Brazil, June 2026

For 3 days, from 9 to 11 June 2026, 8 cities in Brazil had PM2.5 at least twice their usual for the time of year. The worst reading was Nilópolis, Rio de Janeiro, Brazil: 73.2 µg/m³ on 11 June, about 3.6× its usual 20.4. Ended 11 June.

Few fires were detected near these cities on those days. Spreads like this usually come from still weather trapping smoke from heating, traffic and industry, or from dust.
Cities reached8in 1 country
Days39 to 11 June 2026
Worst day9 June6 cities counted
Furthest above usual4.5×Barra da Tijuca

Day by day

9 June 6 cities at twice their usual or more
GuaratinguetáTaubatéSão José dos CamposItaquaquecetubaCubatãoAcariRio de JaneiroJundiaíCampinasPaulíniaLimeiraPiracicabaRio ClaroRibeirão PretoBauruSantosSão PauloFerraz de VasconcelosSanto AndréItaguaíDuque de CaxiasNilópolisBarra da Tijuca
6 Jun7891011121314
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

NilópolisNilópolis, 6 June: 30.7 µg/m³Nilópolis, 7 June: 31.6 µg/m³Nilópolis, 8 June: 43.5 µg/m³Nilópolis, 9 June: 44.8 µg/m³, 2.9× its usual 15.5Nilópolis, 10 June: 31.9 µg/m³Nilópolis, 11 June: 73.2 µg/m³, 3.6× its usual 20.4Nilópolis, 12 June: 57.1 µg/m³Nilópolis, 13 June: no readingNilópolis, 14 June: 18.1 µg/m³Ferraz de Vasconcel…Ferraz de Vasconcelos, 6 June: 15.4 µg/m³Ferraz de Vasconcelos, 7 June: 33.3 µg/m³Ferraz de Vasconcelos, 8 June: 28.5 µg/m³Ferraz de Vasconcelos, 9 June: 38.6 µg/m³, 2.2× its usual 17.8Ferraz de Vasconcelos, 10 June: 37.0 µg/m³, 2.1× its usual 17.9Ferraz de Vasconcelos, 11 June: 18.8 µg/m³Ferraz de Vasconcelos, 12 June: 11.0 µg/m³Ferraz de Vasconcelos, 13 June: 8.0 µg/m³Ferraz de Vasconcelos, 14 June: 6.2 µg/m³Duque de CaxiasDuque de Caxias, 6 June: 19.1 µg/m³Duque de Caxias, 7 June: 24.5 µg/m³Duque de Caxias, 8 June: 27.2 µg/m³Duque de Caxias, 9 June: 37.3 µg/m³, 3.4× its usual 11.1Duque de Caxias, 10 June: 26.2 µg/m³, 2.2× its usual 11.8Duque de Caxias, 11 June: 39.4 µg/m³, 3.5× its usual 11.4Duque de Caxias, 12 June: 33.8 µg/m³Duque de Caxias, 13 June: 14.7 µg/m³Duque de Caxias, 14 June: 8.0 µg/m³Santo AndréSanto André, 6 June: 19.4 µg/m³Santo André, 7 June: 26.9 µg/m³Santo André, 8 June: 24.6 µg/m³Santo André, 9 June: 33.1 µg/m³, 2.1× its usual 15.4Santo André, 10 June: 35.4 µg/m³, 2.3× its usual 15.5Santo André, 11 June: 19.1 µg/m³Santo André, 12 June: 11.3 µg/m³Santo André, 13 June: 7.3 µg/m³Santo André, 14 June: 7.4 µg/m³São PauloSão Paulo, 6 June: 16.9 µg/m³São Paulo, 7 June: 26.6 µg/m³São Paulo, 8 June: 25.4 µg/m³São Paulo, 9 June: 32.9 µg/m³, 2.0× its usual 16.2São Paulo, 10 June: 35.3 µg/m³, 2.2× its usual 16.2São Paulo, 11 June: 16.3 µg/m³São Paulo, 12 June: 12.9 µg/m³São Paulo, 13 June: 8.2 µg/m³São Paulo, 14 June: 6.3 µg/m³SantosSantos, 6 June: 16.8 µg/m³Santos, 7 June: 19.4 µg/m³Santos, 8 June: 18.1 µg/m³Santos, 9 June: 26.4 µg/m³, 2.1× its usual 12.5Santos, 10 June: no readingSantos, 11 June: no readingSantos, 12 June: no readingSantos, 13 June: no readingSantos, 14 June: no readingBarra da TijucaBarra da Tijuca, 6 June: 11.5 µg/m³Barra da Tijuca, 7 June: 17.2 µg/m³Barra da Tijuca, 8 June: 22.3 µg/m³Barra da Tijuca, 9 June: 22.1 µg/m³Barra da Tijuca, 10 June: 15.5 µg/m³Barra da Tijuca, 11 June: 36.1 µg/m³, 4.5× its usual 8.0Barra da Tijuca, 12 June: 30.3 µg/m³Barra da Tijuca, 13 June: no readingBarra da Tijuca, 14 June: 9.2 µg/m³ItaguaíItaguaí, 6 June: 17.2 µg/m³Itaguaí, 7 June: 24.9 µg/m³Itaguaí, 8 June: 28.8 µg/m³Itaguaí, 9 June: 23.0 µg/m³Itaguaí, 10 June: 21.4 µg/m³Itaguaí, 11 June: 33.5 µg/m³, 2.9× its usual 11.4Itaguaí, 12 June: 8.8 µg/m³Itaguaí, 13 June: no readingItaguaí, 14 June: 9.6 µg/m³6 Jun7891011121314
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
Barra da TijucaRio de Janeiro, Brazil1 36.111 June8.04.5×
NilópolisRio de Janeiro, Brazil2 73.211 June20.43.6×
Duque de CaxiasRio de Janeiro, Brazil3 39.411 June11.43.5×
ItaguaíRio de Janeiro, Brazil1 33.511 June11.42.9×
Santo AndréSão Paulo, Brazil2 35.410 June15.52.3×
Ferraz de VasconcelosSão Paulo, Brazil2 38.69 June17.82.2×
São PauloSão Paulo, Brazil2 35.310 June16.22.2×
SantosSão Paulo, Brazil1 26.49 June12.52.1×

Daily means in µg/m³, over the days each city counted in this episode. Highest: its highest of those days. Usual: the city's median for the time of year of that day (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that, with a usual under 5 µg/m³ taken as 5.

Against other episodes in Brazil

Number 14 of 20 episodes in Brazil since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 20.

Use this page

SmogRank, Rio de Janeiro and São Paulo, Brazil, June 2026: 8 cities with PM2.5 at twice their usual or more, 9 to 11 June 2026, smogrank.com/episodes/2026-06-rio-de-janeiro-and-sao-paulo-brazil (accessed 12 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. Fire detections from NASA FIRMS; smoke maps from NOAA HMS. Dust: contains modified Copernicus Atmosphere Monitoring Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.