SmogRank / Episodes / Chile

Biobio and Maule Region, Chile, January 2026

For 3 days, from 19 to 21 January 2026, 10 cities in Chile had PM2.5 at least twice their usual for the time of year. The worst reading was Los Ángeles, Biobio, Chile: 102.1 µg/m³ on 20 January, about 6.7× its usual 15.2.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached10in 1 country
Days319 to 21 January 2026
Worst day21 January10 cities counted
Furthest above usual6.7×Los Ángeles

Day by day

21 January 10 cities at twice their usual or more
TalcahuanoChiguayanteHualpénSan Pedro de la PazCoronelLotaCuranilahueCuricóTemucoRengoRancaguaConcepciónTalcaToméLinaresHualquiNacimientoSan CarlosCauquenesChillánLos Ángeles
16 Jan1718192021222324
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

CauquenesCauquenes, 16 January: 15.0 µg/m³, 1.0× usualCauquenes, 17 January: 17.4 µg/m³, 1.1× usualCauquenes, 18 January: 41.4 µg/m³, 2.7× usualCauquenes, 19 January: 87.8 µg/m³, 5.6× usualCauquenes, 20 January: 66.5 µg/m³, 4.3× usualCauquenes, 21 January: 38.7 µg/m³, 2.5× usualCauquenes, 22 January: 20.0 µg/m³, 1.3× usualCauquenes, 23 January: 15.1 µg/m³, 1.0× usualCauquenes, 24 January: 14.9 µg/m³, 1.0× usualSan CarlosSan Carlos, 16 January: 15.1 µg/m³, 0.8× usualSan Carlos, 17 January: 14.7 µg/m³, 0.8× usualSan Carlos, 18 January: 22.0 µg/m³, 1.2× usualSan Carlos, 19 January: 75.5 µg/m³, 4.0× usualSan Carlos, 20 January: 77.6 µg/m³, 4.1× usualSan Carlos, 21 January: 60.8 µg/m³, 3.2× usualSan Carlos, 22 January: 34.3 µg/m³, 1.8× usualSan Carlos, 23 January: 20.2 µg/m³, 1.1× usualSan Carlos, 24 January: 18.1 µg/m³, 1.0× usualLos ÁngelesLos Ángeles, 16 January: 13.6 µg/m³, 0.9× usualLos Ángeles, 17 January: 16.5 µg/m³, 1.1× usualLos Ángeles, 18 January: 27.5 µg/m³, 1.8× usualLos Ángeles, 19 January: 51.1 µg/m³, 3.4× usualLos Ángeles, 20 January: 102.1 µg/m³, 6.7× usualLos Ángeles, 21 January: 40.9 µg/m³, 2.7× usualLos Ángeles, 22 January: 23.4 µg/m³, 1.5× usualLos Ángeles, 23 January: 18.2 µg/m³, 1.2× usualLos Ángeles, 24 January: 18.4 µg/m³, 1.2× usualChillánChillán, 16 January: 14.5 µg/m³, 0.9× usualChillán, 17 January: 15.4 µg/m³, 1.0× usualChillán, 18 January: 17.3 µg/m³, 1.1× usualChillán, 19 January: 43.1 µg/m³, 2.7× usualChillán, 20 January: 99.0 µg/m³, 6.3× usualChillán, 21 January: 56.7 µg/m³, 3.6× usualChillán, 22 January: 33.7 µg/m³, 2.1× usualChillán, 23 January: 22.0 µg/m³, 1.4× usualChillán, 24 January: 20.6 µg/m³, 1.3× usualHualquiHualqui, 16 January: 14.3 µg/m³, 0.8× usualHualqui, 17 January: 14.4 µg/m³, 0.8× usualHualqui, 18 January: 17.7 µg/m³, 1.0× usualHualqui, 19 January: 36.5 µg/m³, 2.1× usualHualqui, 20 January: 62.5 µg/m³, 3.6× usualHualqui, 21 January: 46.1 µg/m³, 2.7× usualHualqui, 22 January: 24.0 µg/m³, 1.4× usualHualqui, 23 January: 21.3 µg/m³, 1.2× usualHualqui, 24 January: 27.6 µg/m³, 1.6× usualTalcaTalca, 16 January: 16.3 µg/m³, 1.0× usualTalca, 17 January: 13.9 µg/m³, 0.9× usualTalca, 18 January: 18.5 µg/m³, 1.2× usualTalca, 19 January: 33.1 µg/m³, 2.1× usualTalca, 20 January: 38.2 µg/m³, 2.4× usualTalca, 21 January: 32.9 µg/m³, 2.1× usualTalca, 22 January: 26.3 µg/m³, 1.7× usualTalca, 23 January: 25.1 µg/m³, 1.6× usualTalca, 24 January: 22.0 µg/m³, 1.4× usualNacimientoNacimiento, 16 January: no readingNacimiento, 17 January: 16.9 µg/m³, 0.8× usualNacimiento, 18 January: 21.2 µg/m³, 1.0× usualNacimiento, 19 January: 26.5 µg/m³, 1.3× usualNacimiento, 20 January: 82.8 µg/m³, 3.9× usualNacimiento, 21 January: 47.4 µg/m³, 2.2× usualNacimiento, 22 January: 27.5 µg/m³, 1.3× usualNacimiento, 23 January: 23.2 µg/m³, 1.1× usualNacimiento, 24 January: 18.5 µg/m³, 0.9× usualLinaresLinares, 16 January: 12.3 µg/m³, 0.7× usualLinares, 17 January: 13.6 µg/m³, 0.8× usualLinares, 18 January: 16.5 µg/m³, 1.0× usualLinares, 19 January: 28.8 µg/m³, 1.7× usualLinares, 20 January: 42.9 µg/m³, 2.5× usualLinares, 21 January: 46.9 µg/m³, 2.7× usualLinares, 22 January: 32.9 µg/m³, 1.9× usualLinares, 23 January: 22.0 µg/m³, 1.3× usualLinares, 24 January: no readingToméTomé, 16 January: 18.9 µg/m³, 1.1× usualTomé, 17 January: 20.7 µg/m³, 1.2× usualTomé, 18 January: no readingTomé, 19 January: no readingTomé, 20 January: no readingTomé, 21 January: 46.2 µg/m³, 2.7× usualTomé, 22 January: 30.9 µg/m³, 1.8× usualTomé, 23 January: 27.6 µg/m³, 1.6× usualTomé, 24 January: 21.5 µg/m³, 1.2× usualConcepciónConcepción, 16 January: 16.5 µg/m³, 1.1× usualConcepción, 17 January: 16.5 µg/m³, 1.1× usualConcepción, 18 January: 19.2 µg/m³, 1.2× usualConcepción, 19 January: 25.2 µg/m³, 1.6× usualConcepción, 20 January: 30.9 µg/m³, 2.0× usualConcepción, 21 January: 32.0 µg/m³, 2.0× usualConcepción, 22 January: 44.8 µg/m³, 2.9× usualConcepción, 23 January: 35.0 µg/m³, 2.2× usualConcepción, 24 January: 20.6 µg/m³, 1.3× usual16 Jan1718192021222324
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, Chile3 102.120 January15.26.7×
ChillánÑuble, Chile3 99.020 January15.86.3×
CauquenesMaule Region, Chile3 87.819 January15.65.6×
San CarlosÑuble, Chile3 77.620 January18.94.1×
NacimientoBiobio, Chile2 82.820 January21.23.9×
HualquiBiobio, Chile3 62.520 January17.23.6×
ConcepciónBiobio, Chile1 44.822 January15.72.9×
LinaresMaule Region, Chile2 46.921 January17.32.7×
ToméBiobio, Chile1 46.221 January17.42.7×
TalcaMaule Region, Chile3 38.220 January15.92.4×

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 8 of 11 episodes in Chile since our records began, by cities reached.

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

Use this page

SmogRank, Biobio and Maule Region, Chile, January 2026: 10 cities with PM2.5 at twice their usual or more, 19 to 21 January 2026, smogrank.com/episodes/2026-01-biobio-and-maule-region-chile (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.