SmogRank / Episodes / Chile

Biobio and Ñuble, Chile, May 2024

For 3 days, from 10 to 12 May 2024, 9 cities in Chile had PM2.5 at least twice their usual for the time of year. The worst reading was Nacimiento, Biobio, Chile: 139.0 µg/m³ on 12 May, about 2.2× its usual 63.4.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached9in 1 country
Days310 to 12 May 2024
Worst day10 May6 cities counted
Furthest above usual3.0×Los Ángeles

Day by day

10 May 6 cities at twice their usual or more
TemucoValdiviaLa UniónCuranilahueOsornoCoronelChiguayanteConcepciónToméPuerto MonttSan Pedro de la PazPuerto VarasNacimientoSan CarlosVillarricaHualpénTalcahuanoChillánLos Ángeles
7 May89101112131415
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

HualpénHualpén, 7 May: 30.5 µg/m³, 0.7× usualHualpén, 8 May: 94.3 µg/m³, 2.0× usualHualpén, 9 May: 67.7 µg/m³, 1.5× usualHualpén, 10 May: 121.0 µg/m³, 2.6× usualHualpén, 11 May: 110.0 µg/m³, 2.4× usualHualpén, 12 May: 102.0 µg/m³, 2.2× usualHualpén, 13 May: 62.6 µg/m³, 1.3× usualHualpén, 14 May: 93.3 µg/m³, 2.0× usualHualpén, 15 May: 129.0 µg/m³, 2.8× usualTalcahuanoTalcahuano, 7 May: 20.6 µg/m³, 0.6× usualTalcahuano, 8 May: 69.8 µg/m³, 2.1× usualTalcahuano, 9 May: 62.7 µg/m³, 1.9× usualTalcahuano, 10 May: 62.1 µg/m³, 1.9× usualTalcahuano, 11 May: 95.3 µg/m³, 2.9× usualTalcahuano, 12 May: 88.7 µg/m³, 2.7× usualTalcahuano, 13 May: 49.7 µg/m³, 1.5× usualTalcahuano, 14 May: 51.7 µg/m³, 1.6× usualTalcahuano, 15 May: 104.2 µg/m³, 3.1× usualNacimientoNacimiento, 7 May: 67.0 µg/m³, 1.1× usualNacimiento, 8 May: 53.3 µg/m³, 0.8× usualNacimiento, 9 May: 143.0 µg/m³, 2.3× usualNacimiento, 10 May: 109.0 µg/m³, 1.7× usualNacimiento, 11 May: 100.3 µg/m³, 1.6× usualNacimiento, 12 May: 139.0 µg/m³, 2.2× usualNacimiento, 13 May: 82.2 µg/m³, 1.3× usualNacimiento, 14 May: 126.4 µg/m³, 2.0× usualNacimiento, 15 May: 120.0 µg/m³, 1.9× usualVillarricaVillarrica, 7 May: no readingVillarrica, 8 May: no readingVillarrica, 9 May: 39.2 µg/m³, 0.9× usualVillarrica, 10 May: 104.0 µg/m³, 2.5× usualVillarrica, 11 May: 108.0 µg/m³, 2.5× usualVillarrica, 12 May: 53.5 µg/m³, 1.3× usualVillarrica, 13 May: 41.3 µg/m³, 1.0× usualVillarrica, 14 May: 73.4 µg/m³, 1.7× usualVillarrica, 15 May: 92.9 µg/m³, 2.2× usualLos ÁngelesLos Ángeles, 7 May: 15.3 µg/m³, 0.5× usualLos Ángeles, 8 May: 30.5 µg/m³, 0.9× usualLos Ángeles, 9 May: 58.8 µg/m³, 1.8× usualLos Ángeles, 10 May: 99.1 µg/m³, 3.0× usualLos Ángeles, 11 May: 91.9 µg/m³, 2.8× usualLos Ángeles, 12 May: 64.1 µg/m³, 1.9× usualLos Ángeles, 13 May: 27.1 µg/m³, 0.8× usualLos Ángeles, 14 May: 44.2 µg/m³, 1.3× usualLos Ángeles, 15 May: 119.9 µg/m³, 3.6× usualPuerto VarasPuerto Varas, 7 May: 22.6 µg/m³, 0.5× usualPuerto Varas, 8 May: 33.7 µg/m³, 0.8× usualPuerto Varas, 9 May: 38.3 µg/m³, 0.9× usualPuerto Varas, 10 May: 91.4 µg/m³, 2.1× usualPuerto Varas, 11 May: 56.9 µg/m³, 1.3× usualPuerto Varas, 12 May: 62.0 µg/m³, 1.4× usualPuerto Varas, 13 May: 87.3 µg/m³, 2.0× usualPuerto Varas, 14 May: 74.4 µg/m³, 1.7× usualPuerto Varas, 15 May: 52.2 µg/m³, 1.2× usualChillánChillán, 7 May: 19.7 µg/m³, 0.5× usualChillán, 8 May: 28.4 µg/m³, 0.7× usualChillán, 9 May: 45.2 µg/m³, 1.1× usualChillán, 10 May: 87.1 µg/m³, 2.2× usualChillán, 11 May: 118.3 µg/m³, 2.9× usualChillán, 12 May: 104.2 µg/m³, 2.6× usualChillán, 13 May: 44.0 µg/m³, 1.1× usualChillán, 14 May: 102.6 µg/m³, 2.5× usualChillán, 15 May: 87.8 µg/m³, 2.2× usualSan Pedro de la PazSan Pedro de la Paz, 7 May: 19.2 µg/m³, 0.8× usualSan Pedro de la Paz, 8 May: 34.3 µg/m³, 1.3× usualSan Pedro de la Paz, 9 May: 29.9 µg/m³, 1.2× usualSan Pedro de la Paz, 10 May: 53.7 µg/m³, 2.1× usualSan Pedro de la Paz, 11 May: 38.0 µg/m³, 1.5× usualSan Pedro de la Paz, 12 May: 38.5 µg/m³, 1.5× usualSan Pedro de la Paz, 13 May: 30.3 µg/m³, 1.2× usualSan Pedro de la Paz, 14 May: 37.6 µg/m³, 1.5× usualSan Pedro de la Paz, 15 May: 46.3 µg/m³, 1.8× usualSan CarlosSan Carlos, 7 May: 14.7 µg/m³, 0.3× usualSan Carlos, 8 May: 25.3 µg/m³, 0.6× usualSan Carlos, 9 May: 40.9 µg/m³, 0.9× usualSan Carlos, 10 May: 86.1 µg/m³, 2.0× usualSan Carlos, 11 May: 102.0 µg/m³, 2.3× usualSan Carlos, 12 May: 73.1 µg/m³, 1.7× usualSan Carlos, 13 May: 58.2 µg/m³, 1.3× usualSan Carlos, 14 May: 113.0 µg/m³, 2.6× usualSan Carlos, 15 May: 56.2 µg/m³, 1.3× usual7 May89101112131415
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
Los ÁngelesBiobio, Chile2 119.915 May33.03.6×
TalcahuanoBiobio, Chile2 104.215 May33.23.1×
ChillánÑuble, Chile3 118.311 May40.52.9×
HualpénBiobio, Chile3 129.015 May46.62.8×
San CarlosÑuble, Chile1 113.014 May43.82.6×
VillarricaAraucania, Chile2 108.011 May42.42.5×
NacimientoBiobio, Chile1 143.09 May63.42.3×
San Pedro de la PazBiobio, Chile1 53.710 May25.52.1×
Puerto VarasLos Lagos Region, Chile1 91.410 May44.02.1×

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 Chile

Number 25 of 30 episodes in Chile since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 30.

Use this page

SmogRank, Biobio and Ñuble, Chile, May 2024: 9 cities with PM2.5 at twice their usual or more, 10 to 12 May 2024, smogrank.com/episodes/2024-05-biobio-and-nuble-chile (accessed 3 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.