SmogRank / Episodes / Slovakia

Eastern Europe, December 2023

For 6 days, from 16 to 21 December 2023, 66 cities in Slovakia, Austria, Czechia and 8 more countries had PM2.5 at least twice their usual for the time of year. The worst reading was Sarajevo, Federation of B&H, Bosnia and Herzegovina: 230.0 µg/m³ on 20 December, about 5.1× its usual 44.8. Ended 21 December.

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 reached66in 11 countries
Days616 to 21 December 2023
Worst day19 December50 cities counted
Furthest above usual5.1×Sarajevo

Day by day

19 December 50 cities at twice their usual or more
LiberpolisDunaújvárosVeszprémNitraZvolenŽiar nad HronomKazincbarcikaTrnavaRevúcaKarlova VesMartinSmižanySpišská Nová VesŽilinaVeľká LomnicaBad VöslauLeibnitzWeizZlínPrešovMikulovKroměřížTřinecTullnFrýdek-MístekČeský TěšínCieszynPřerovHavířovStudénkaOstravaBohumínSankt PöltenOlomoucIlindenWodzisław ŚląskiWolfsbergZnojmoOpavaRijekaKlagenfurt am WörtherseeAmstettenKochaniDejKavadarciSofiaCeglie MessapicaSankt ValentinSan Pietro VernoticoSteyrEnnsAnsfeldenTraunCivitanova MarchePorto Potenza PicenaAttnang-PuchheimFalconara MarittimaChiaravalleJesiThessaloníkiPylaíaPassauPesaroSalzburgPragueSaalfelden am Steinernen MeerLiberecBerounGabrovoBurghausenTraunreutTrostberg an der AlzJilavaPilsenDěčínÚstí nad LabemKiefersfeldenTepliceMostKadaňBorgo ValsuganaLaivesBolzanoSokolovSchwandorf in BayernKelheimMunichNeustadt an der DonauTrentoWeidenRoveretoStarnbergMarktredwitzGreizAltenburgAugsburgGeraNurembergKempten (Allgäu)WeißenfelsOettingen in BayernJenaSaalfeldBambergAnsbachCoburgLa SpeziaWeimarNeu-UlmBad WindsheimUlmAalenLindauBiberach an der RißErfurtSuhlFriedrichshafenMeiningenSondershausenWürzburgBastiaKreuzlingenKonstanzLauda-KönigshofenEisenachMühlhausenReutlingenFilderstadtStuttgartLudwigsburgHeilbronnFuldaWitzenhausenKasselViennaLitvínovSenicaHainburg an der DonauValašské MeziříčíVranov nad TopľouVoitsbergRuseGrazVelesSkopjePerchtoldsdorfTrenčínKolárovoAnconaEisenstadtBucharestCluj-NapocaMiskolcGroß-EnzersdorfCasertaWelsSlatinaŽideniceBratislavaMladá BoleslavBrnoSzegedKošiceNyíregyházaČaňaTetovoLinzPartizánskeEsztergomPrievidzaPécsNaplesMödlingKlosterneuburgCapannoriSalernoIaşiBanská BystricaBitolaSninaHolbocaMoravská TřebováHaskovoBeneventoNišHradec KrálovéHandlováGyőrBaloteştiPardubiceCraiovaNovi SadBotevgradHumennéRužomberokČeské BudějoviceBelgradeBanja LukaPristinaSarajevo
13 Dec1415161718192021222324
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

ČaňaČaňa, 13 December: 23.9 µg/m³Čaňa, 14 December: 30.3 µg/m³Čaňa, 15 December: 20.4 µg/m³Čaňa, 16 December: 50.9 µg/m³, 2.3× its usual 22.4Čaňa, 17 December: 37.4 µg/m³Čaňa, 18 December: 22.3 µg/m³Čaňa, 19 December: 23.3 µg/m³Čaňa, 20 December: 17.3 µg/m³Čaňa, 21 December: 15.1 µg/m³Čaňa, 22 December: 5.9 µg/m³Čaňa, 23 December: 4.1 µg/m³Čaňa, 24 December: 9.5 µg/m³HandlováHandlová, 13 December: 11.3 µg/m³Handlová, 14 December: 29.7 µg/m³Handlová, 15 December: 10.9 µg/m³Handlová, 16 December: 37.9 µg/m³, 3.1× its usual 12.4Handlová, 17 December: 24.4 µg/m³Handlová, 18 December: 41.4 µg/m³, 3.1× its usual 13.2Handlová, 19 December: 37.8 µg/m³, 2.9× its usual 12.9Handlová, 20 December: 20.8 µg/m³Handlová, 21 December: 2.9 µg/m³Handlová, 22 December: 2.7 µg/m³Handlová, 23 December: 2.7 µg/m³Handlová, 24 December: 6.2 µg/m³PrievidzaPrievidza, 13 December: 17.3 µg/m³Prievidza, 14 December: 21.5 µg/m³Prievidza, 15 December: 14.4 µg/m³Prievidza, 16 December: 30.6 µg/m³, 2.1× its usual 14.9Prievidza, 17 December: 38.9 µg/m³, 2.5× its usual 15.8Prievidza, 18 December: 23.4 µg/m³Prievidza, 19 December: 37.3 µg/m³, 2.4× its usual 15.8Prievidza, 20 December: 39.0 µg/m³, 2.4× its usual 16.2Prievidza, 21 December: 12.7 µg/m³Prievidza, 22 December: 5.5 µg/m³Prievidza, 23 December: 6.2 µg/m³Prievidza, 24 December: 12.3 µg/m³Valašské MeziříčíValašské Meziříčí, 13 December: 15.7 µg/m³Valašské Meziříčí, 14 December: 29.0 µg/m³Valašské Meziříčí, 15 December: 24.3 µg/m³Valašské Meziříčí, 16 December: 30.6 µg/m³, 2.1× its usual 14.7Valašské Meziříčí, 17 December: 17.1 µg/m³Valašské Meziříčí, 18 December: 16.6 µg/m³Valašské Meziříčí, 19 December: 12.6 µg/m³Valašské Meziříčí, 20 December: 12.2 µg/m³Valašské Meziříčí, 21 December: no readingValašské Meziříčí, 22 December: no readingValašské Meziříčí, 23 December: no readingValašské Meziříčí, 24 December: 5.5 µg/m³TrenčínTrenčín, 13 December: 23.3 µg/m³Trenčín, 14 December: 21.5 µg/m³Trenčín, 15 December: 9.0 µg/m³Trenčín, 16 December: 29.7 µg/m³, 2.2× its usual 13.7Trenčín, 17 December: 23.1 µg/m³Trenčín, 18 December: 9.4 µg/m³Trenčín, 19 December: 21.2 µg/m³Trenčín, 20 December: 16.4 µg/m³Trenčín, 21 December: 7.1 µg/m³Trenčín, 22 December: 8.3 µg/m³Trenčín, 23 December: 8.4 µg/m³Trenčín, 24 December: 11.5 µg/m³MiskolcMiskolc, 13 December: 21.7 µg/m³Miskolc, 14 December: 31.1 µg/m³Miskolc, 15 December: 42.8 µg/m³Miskolc, 16 December: 40.1 µg/m³Miskolc, 17 December: 55.7 µg/m³, 2.2× its usual 25.5Miskolc, 18 December: 29.9 µg/m³Miskolc, 19 December: 25.2 µg/m³Miskolc, 20 December: 25.5 µg/m³Miskolc, 21 December: 15.5 µg/m³Miskolc, 22 December: 8.6 µg/m³Miskolc, 23 December: 7.1 µg/m³Miskolc, 24 December: 9.2 µg/m³Banská BystricaBanská Bystrica, 13 December: 27.0 µg/m³Banská Bystrica, 14 December: 28.9 µg/m³Banská Bystrica, 15 December: 14.8 µg/m³Banská Bystrica, 16 December: 24.2 µg/m³Banská Bystrica, 17 December: 36.6 µg/m³, 2.3× its usual 15.7Banská Bystrica, 18 December: 28.6 µg/m³Banská Bystrica, 19 December: 46.9 µg/m³, 2.8× its usual 16.7Banská Bystrica, 20 December: 26.6 µg/m³Banská Bystrica, 21 December: 5.8 µg/m³Banská Bystrica, 22 December: 3.6 µg/m³Banská Bystrica, 23 December: 3.4 µg/m³Banská Bystrica, 24 December: 11.5 µg/m³KošiceKošice, 13 December: 15.8 µg/m³Košice, 14 December: 17.3 µg/m³Košice, 15 December: 13.1 µg/m³Košice, 16 December: 32.6 µg/m³Košice, 17 December: 41.3 µg/m³, 2.3× its usual 18.0Košice, 18 December: 24.7 µg/m³Košice, 19 December: 27.1 µg/m³Košice, 20 December: 16.9 µg/m³Košice, 21 December: 14.3 µg/m³Košice, 22 December: 8.2 µg/m³Košice, 23 December: 3.2 µg/m³Košice, 24 December: 10.3 µg/m³České BudějoviceČeské Budějovice, 13 December: 10.8 µg/m³České Budějovice, 14 December: 19.0 µg/m³České Budějovice, 15 December: 9.0 µg/m³České Budějovice, 16 December: 12.2 µg/m³České Budějovice, 17 December: 25.3 µg/m³, 2.3× its usual 10.9České Budějovice, 18 December: 37.9 µg/m³, 3.5× its usual 10.9České Budějovice, 19 December: 25.5 µg/m³, 2.3× its usual 10.9České Budějovice, 20 December: no readingČeské Budějovice, 21 December: no readingČeské Budějovice, 22 December: no readingČeské Budějovice, 23 December: no readingČeské Budějovice, 24 December: no readingSarajevoSarajevo, 13 December: 36.3 µg/m³Sarajevo, 14 December: 25.5 µg/m³Sarajevo, 15 December: 25.2 µg/m³Sarajevo, 16 December: 25.9 µg/m³Sarajevo, 17 December: 72.5 µg/m³Sarajevo, 18 December: 133.0 µg/m³, 2.9× its usual 45.1Sarajevo, 19 December: 222.0 µg/m³, 4.9× its usual 45.0Sarajevo, 20 December: 230.0 µg/m³, 5.1× its usual 44.8Sarajevo, 21 December: 182.0 µg/m³Sarajevo, 22 December: 42.9 µg/m³Sarajevo, 23 December: 40.8 µg/m³Sarajevo, 24 December: 44.7 µg/m³Banja LukaBanja Luka, 13 December: 29.7 µg/m³Banja Luka, 14 December: 43.2 µg/m³Banja Luka, 15 December: 40.7 µg/m³Banja Luka, 16 December: 86.0 µg/m³Banja Luka, 17 December: 112.0 µg/m³Banja Luka, 18 December: 189.0 µg/m³, 3.7× its usual 51.7Banja Luka, 19 December: 190.0 µg/m³, 3.6× its usual 53.3Banja Luka, 20 December: 144.0 µg/m³, 2.7× its usual 53.4Banja Luka, 21 December: 118.0 µg/m³Banja Luka, 22 December: 45.5 µg/m³Banja Luka, 23 December: 131.0 µg/m³Banja Luka, 24 December: 126.0 µg/m³NišNiš, 13 December: 35.3 µg/m³Niš, 14 December: 35.9 µg/m³Niš, 15 December: 20.9 µg/m³Niš, 16 December: 20.2 µg/m³Niš, 17 December: 54.6 µg/m³Niš, 18 December: 88.3 µg/m³, 2.2× its usual 40.3Niš, 19 December: 96.8 µg/m³, 2.4× its usual 40.8Niš, 20 December: 120.5 µg/m³, 3.0× its usual 40.3Niš, 21 December: 71.3 µg/m³Niš, 22 December: 81.2 µg/m³Niš, 23 December: 48.7 µg/m³Niš, 24 December: 105.5 µg/m³BelgradeBelgrade, 13 December: 22.8 µg/m³Belgrade, 14 December: 16.6 µg/m³Belgrade, 15 December: 26.4 µg/m³Belgrade, 16 December: 25.9 µg/m³Belgrade, 17 December: 52.8 µg/m³Belgrade, 18 December: 89.4 µg/m³, 3.2× its usual 27.6Belgrade, 19 December: 95.3 µg/m³, 3.5× its usual 27.6Belgrade, 20 December: 90.1 µg/m³, 3.2× its usual 27.8Belgrade, 21 December: 26.5 µg/m³Belgrade, 22 December: 16.1 µg/m³Belgrade, 23 December: 14.4 µg/m³Belgrade, 24 December: 40.9 µg/m³BotevgradBotevgrad, 13 December: 18.4 µg/m³Botevgrad, 14 December: 9.8 µg/m³Botevgrad, 15 December: 12.8 µg/m³Botevgrad, 16 December: 14.5 µg/m³Botevgrad, 17 December: 26.3 µg/m³Botevgrad, 18 December: 48.3 µg/m³, 2.1× its usual 23.0Botevgrad, 19 December: 71.3 µg/m³, 3.2× its usual 22.2Botevgrad, 20 December: 56.8 µg/m³, 2.6× its usual 22.1Botevgrad, 21 December: 31.4 µg/m³Botevgrad, 22 December: 8.9 µg/m³Botevgrad, 23 December: 7.6 µg/m³Botevgrad, 24 December: 13.1 µg/m³Novi SadNovi Sad, 13 December: 20.4 µg/m³Novi Sad, 14 December: 16.2 µg/m³Novi Sad, 15 December: 21.3 µg/m³Novi Sad, 16 December: 25.0 µg/m³Novi Sad, 17 December: 29.3 µg/m³Novi Sad, 18 December: 63.8 µg/m³, 3.0× its usual 21.4Novi Sad, 19 December: 68.7 µg/m³, 3.2× its usual 21.5Novi Sad, 20 December: 64.0 µg/m³, 2.9× its usual 21.7Novi Sad, 21 December: 15.0 µg/m³Novi Sad, 22 December: 10.8 µg/m³Novi Sad, 23 December: 8.1 µg/m³Novi Sad, 24 December: 36.1 µg/m³Moravská TřebováMoravská Třebová, 13 December: 29.7 µg/m³Moravská Třebová, 14 December: 18.8 µg/m³Moravská Třebová, 15 December: 15.7 µg/m³Moravská Třebová, 16 December: 12.9 µg/m³Moravská Třebová, 17 December: 24.0 µg/m³Moravská Třebová, 18 December: 40.6 µg/m³, 2.2× its usual 18.4Moravská Třebová, 19 December: 53.1 µg/m³, 2.9× its usual 18.2Moravská Třebová, 20 December: 21.4 µg/m³Moravská Třebová, 21 December: no readingMoravská Třebová, 22 December: no readingMoravská Třebová, 23 December: 8.1 µg/m³Moravská Třebová, 24 December: 7.1 µg/m³IaşiIaşi, 13 December: 20.2 µg/m³Iaşi, 14 December: 15.6 µg/m³Iaşi, 15 December: 9.4 µg/m³Iaşi, 16 December: 14.9 µg/m³Iaşi, 17 December: 25.7 µg/m³Iaşi, 18 December: 33.1 µg/m³, 2.1× its usual 15.9Iaşi, 19 December: 34.6 µg/m³, 2.1× its usual 16.3Iaşi, 20 December: 43.8 µg/m³, 2.7× its usual 16.5Iaşi, 21 December: 31.9 µg/m³Iaşi, 22 December: 18.1 µg/m³Iaşi, 23 December: 13.9 µg/m³Iaşi, 24 December: 19.1 µg/m³Cluj-NapocaCluj-Napoca, 13 December: 22.7 µg/m³Cluj-Napoca, 14 December: 11.3 µg/m³Cluj-Napoca, 15 December: 11.4 µg/m³Cluj-Napoca, 16 December: 14.2 µg/m³Cluj-Napoca, 17 December: 34.3 µg/m³Cluj-Napoca, 18 December: 43.4 µg/m³, 2.2× its usual 19.6Cluj-Napoca, 19 December: 21.8 µg/m³Cluj-Napoca, 20 December: 38.3 µg/m³Cluj-Napoca, 21 December: 39.6 µg/m³Cluj-Napoca, 22 December: 10.4 µg/m³Cluj-Napoca, 23 December: 3.8 µg/m³Cluj-Napoca, 24 December: 24.5 µg/m³Hradec KrálovéHradec Králové, 13 December: 14.4 µg/m³Hradec Králové, 14 December: 16.4 µg/m³Hradec Králové, 15 December: 6.6 µg/m³Hradec Králové, 16 December: 10.3 µg/m³Hradec Králové, 17 December: 13.7 µg/m³Hradec Králové, 18 December: 26.9 µg/m³, 2.1× its usual 12.9Hradec Králové, 19 December: 40.3 µg/m³, 3.1× its usual 12.8Hradec Králové, 20 December: 7.9 µg/m³Hradec Králové, 21 December: 2.5 µg/m³Hradec Králové, 22 December: 2.4 µg/m³Hradec Králové, 23 December: 2.4 µg/m³Hradec Králové, 24 December: 3.7 µg/m³PardubicePardubice, 13 December: 13.6 µg/m³Pardubice, 14 December: 18.5 µg/m³Pardubice, 15 December: 10.0 µg/m³Pardubice, 16 December: 9.6 µg/m³Pardubice, 17 December: 20.4 µg/m³Pardubice, 18 December: 39.6 µg/m³, 3.2× its usual 12.2Pardubice, 19 December: 34.7 µg/m³, 2.8× its usual 12.2Pardubice, 20 December: 6.1 µg/m³Pardubice, 21 December: no readingPardubice, 22 December: no readingPardubice, 23 December: 3.2 µg/m³Pardubice, 24 December: no readingEisenstadtEisenstadt, 13 December: 23.2 µg/m³Eisenstadt, 14 December: 8.9 µg/m³Eisenstadt, 15 December: 10.2 µg/m³Eisenstadt, 16 December: 12.7 µg/m³Eisenstadt, 17 December: 22.6 µg/m³Eisenstadt, 18 December: 32.7 µg/m³, 2.2× its usual 14.9Eisenstadt, 19 December: 34.8 µg/m³, 2.2× its usual 15.7Eisenstadt, 20 December: 15.5 µg/m³Eisenstadt, 21 December: 11.3 µg/m³Eisenstadt, 22 December: 3.8 µg/m³Eisenstadt, 23 December: 3.7 µg/m³Eisenstadt, 24 December: 3.5 µg/m³Mladá BoleslavMladá Boleslav, 13 December: 15.6 µg/m³Mladá Boleslav, 14 December: 14.4 µg/m³Mladá Boleslav, 15 December: 8.2 µg/m³Mladá Boleslav, 16 December: 11.0 µg/m³Mladá Boleslav, 17 December: 15.2 µg/m³Mladá Boleslav, 18 December: 33.5 µg/m³, 2.3× its usual 14.4Mladá Boleslav, 19 December: 30.1 µg/m³, 2.1× its usual 14.4Mladá Boleslav, 20 December: 4.9 µg/m³Mladá Boleslav, 21 December: no readingMladá Boleslav, 22 December: 5.0 µg/m³Mladá Boleslav, 23 December: 4.9 µg/m³Mladá Boleslav, 24 December: no readingKolárovoKolárovo, 13 December: 12.7 µg/m³Kolárovo, 14 December: 15.5 µg/m³Kolárovo, 15 December: 12.9 µg/m³Kolárovo, 16 December: 18.2 µg/m³Kolárovo, 17 December: 19.3 µg/m³Kolárovo, 18 December: 29.1 µg/m³, 2.1× its usual 14.1Kolárovo, 19 December: 31.8 µg/m³, 2.2× its usual 14.7Kolárovo, 20 December: 18.0 µg/m³Kolárovo, 21 December: 22.4 µg/m³Kolárovo, 22 December: 5.9 µg/m³Kolárovo, 23 December: 4.5 µg/m³Kolárovo, 24 December: 5.9 µg/m³LinzLinz, 13 December: 15.0 µg/m³Linz, 14 December: 8.0 µg/m³Linz, 15 December: 8.9 µg/m³Linz, 16 December: 16.3 µg/m³Linz, 17 December: 19.9 µg/m³Linz, 18 December: 30.8 µg/m³, 2.4× its usual 12.9Linz, 19 December: 28.4 µg/m³, 2.2× its usual 13.1Linz, 20 December: 9.8 µg/m³Linz, 21 December: 1.6 µg/m³Linz, 22 December: 1.4 µg/m³Linz, 23 December: 0.7 µg/m³Linz, 24 December: 1.2 µg/m³BratislavaBratislava, 13 December: 12.4 µg/m³Bratislava, 14 December: 11.5 µg/m³Bratislava, 15 December: 6.7 µg/m³Bratislava, 16 December: 9.5 µg/m³Bratislava, 17 December: 11.5 µg/m³Bratislava, 18 December: 25.9 µg/m³, 2.0× its usual 12.8Bratislava, 19 December: 30.0 µg/m³, 2.3× its usual 13.0Bratislava, 20 December: 9.7 µg/m³Bratislava, 21 December: 12.4 µg/m³Bratislava, 22 December: 2.2 µg/m³Bratislava, 23 December: 2.2 µg/m³Bratislava, 24 December: 1.6 µg/m³TetovoTetovo, 13 December: 104.0 µg/m³Tetovo, 14 December: 43.4 µg/m³Tetovo, 15 December: 23.0 µg/m³Tetovo, 16 December: 17.3 µg/m³Tetovo, 17 December: 36.2 µg/m³Tetovo, 18 December: 119.0 µg/m³Tetovo, 19 December: 154.0 µg/m³, 2.3× its usual 66.3Tetovo, 20 December: 130.0 µg/m³Tetovo, 21 December: 121.0 µg/m³Tetovo, 22 December: 57.6 µg/m³Tetovo, 23 December: 21.8 µg/m³Tetovo, 24 December: 56.6 µg/m³BitolaBitola, 13 December: 65.6 µg/m³Bitola, 14 December: 13.5 µg/m³Bitola, 15 December: 23.9 µg/m³Bitola, 16 December: 15.7 µg/m³Bitola, 17 December: 31.0 µg/m³Bitola, 18 December: 79.8 µg/m³Bitola, 19 December: 119.1 µg/m³, 2.8× its usual 43.3Bitola, 20 December: 64.6 µg/m³Bitola, 21 December: 76.2 µg/m³Bitola, 22 December: 51.9 µg/m³Bitola, 23 December: 36.6 µg/m³Bitola, 24 December: 20.1 µg/m³VelesVeles, 13 December: 41.1 µg/m³Veles, 14 December: 20.5 µg/m³Veles, 15 December: 10.2 µg/m³Veles, 16 December: 8.1 µg/m³Veles, 17 December: 39.4 µg/m³Veles, 18 December: 79.9 µg/m³Veles, 19 December: 95.8 µg/m³, 2.1× its usual 45.0Veles, 20 December: 86.9 µg/m³Veles, 21 December: 53.1 µg/m³Veles, 22 December: 53.1 µg/m³Veles, 23 December: 65.2 µg/m³Veles, 24 December: 71.1 µg/m³PristinaPristina, 13 December: no readingPristina, 14 December: 9.3 µg/m³Pristina, 15 December: 1.8 µg/m³Pristina, 16 December: no readingPristina, 17 December: no readingPristina, 18 December: no readingPristina, 19 December: 74.3 µg/m³, 3.5× its usual 21.3Pristina, 20 December: 94.2 µg/m³, 4.6× its usual 20.4Pristina, 21 December: 53.4 µg/m³Pristina, 22 December: 32.2 µg/m³Pristina, 23 December: 13.3 µg/m³Pristina, 24 December: 17.3 µg/m³BeneventoBenevento, 13 December: 18.5 µg/m³Benevento, 14 December: 15.7 µg/m³Benevento, 15 December: 10.0 µg/m³Benevento, 16 December: 9.1 µg/m³Benevento, 17 December: 22.0 µg/m³Benevento, 18 December: 42.3 µg/m³Benevento, 19 December: 47.7 µg/m³, 2.1× its usual 22.7Benevento, 20 December: 65.8 µg/m³, 2.9× its usual 22.7Benevento, 21 December: 46.9 µg/m³Benevento, 22 December: 26.0 µg/m³Benevento, 23 December: 26.5 µg/m³Benevento, 24 December: 23.5 µg/m³HaskovoHaskovo, 13 December: 45.0 µg/m³Haskovo, 14 December: 61.6 µg/m³Haskovo, 15 December: 11.9 µg/m³Haskovo, 16 December: no readingHaskovo, 17 December: no readingHaskovo, 18 December: 41.5 µg/m³Haskovo, 19 December: 52.8 µg/m³, 2.4× its usual 21.7Haskovo, 20 December: 63.5 µg/m³, 2.9× its usual 21.8Haskovo, 21 December: 45.3 µg/m³, 2.1× its usual 21.8Haskovo, 22 December: no readingHaskovo, 23 December: 14.6 µg/m³Haskovo, 24 December: 19.4 µg/m³RužomberokRužomberok, 13 December: 31.4 µg/m³Ružomberok, 14 December: 16.9 µg/m³Ružomberok, 15 December: 9.9 µg/m³Ružomberok, 16 December: 17.1 µg/m³Ružomberok, 17 December: 21.3 µg/m³Ružomberok, 18 December: 19.2 µg/m³Ružomberok, 19 December: 58.8 µg/m³, 3.3× its usual 17.7Ružomberok, 20 December: 29.2 µg/m³Ružomberok, 21 December: 5.3 µg/m³Ružomberok, 22 December: 5.0 µg/m³Ružomberok, 23 December: 9.7 µg/m³Ružomberok, 24 December: 34.8 µg/m³HumennéHumenné, 13 December: 21.7 µg/m³Humenné, 14 December: 18.0 µg/m³Humenné, 15 December: 14.5 µg/m³Humenné, 16 December: 27.4 µg/m³Humenné, 17 December: 33.4 µg/m³Humenné, 18 December: 32.7 µg/m³Humenné, 19 December: 54.9 µg/m³, 3.3× its usual 16.8Humenné, 20 December: 51.1 µg/m³, 3.0× its usual 16.8Humenné, 21 December: 20.5 µg/m³Humenné, 22 December: 14.3 µg/m³Humenné, 23 December: 9.9 µg/m³Humenné, 24 December: 16.2 µg/m³BaloteştiBaloteşti, 13 December: 25.3 µg/m³Baloteşti, 14 December: 26.6 µg/m³Baloteşti, 15 December: 9.9 µg/m³Baloteşti, 16 December: 8.0 µg/m³Baloteşti, 17 December: 19.3 µg/m³Baloteşti, 18 December: 25.1 µg/m³Baloteşti, 19 December: 38.0 µg/m³, 2.4× its usual 16.0Baloteşti, 20 December: 51.0 µg/m³, 3.1× its usual 16.2Baloteşti, 21 December: 35.0 µg/m³, 2.2× its usual 16.2Baloteşti, 22 December: 24.5 µg/m³Baloteşti, 23 December: 4.3 µg/m³Baloteşti, 24 December: 13.8 µg/m³CraiovaCraiova, 13 December: 20.9 µg/m³Craiova, 14 December: 17.7 µg/m³Craiova, 15 December: 9.6 µg/m³Craiova, 16 December: 13.1 µg/m³Craiova, 17 December: 13.8 µg/m³Craiova, 18 December: 20.0 µg/m³Craiova, 19 December: 49.9 µg/m³, 3.2× its usual 15.8Craiova, 20 December: 46.4 µg/m³, 2.9× its usual 16.2Craiova, 21 December: 29.7 µg/m³Craiova, 22 December: 19.8 µg/m³Craiova, 23 December: 4.4 µg/m³Craiova, 24 December: 4.6 µg/m³GyőrGyőr, 13 December: 21.1 µg/m³Győr, 14 December: 18.2 µg/m³Győr, 15 December: 10.9 µg/m³Győr, 16 December: 15.2 µg/m³Győr, 17 December: 15.3 µg/m³Győr, 18 December: 25.8 µg/m³Győr, 19 December: 48.7 µg/m³, 3.1× its usual 15.9Győr, 20 December: 27.5 µg/m³Győr, 21 December: 22.8 µg/m³Győr, 22 December: 3.7 µg/m³Győr, 23 December: 3.9 µg/m³Győr, 24 December: 6.8 µg/m³NaplesNaples, 13 December: 7.6 µg/m³Naples, 14 December: 12.1 µg/m³Naples, 15 December: 7.8 µg/m³Naples, 16 December: 5.5 µg/m³Naples, 17 December: 9.3 µg/m³Naples, 18 December: 26.4 µg/m³Naples, 19 December: 39.8 µg/m³, 2.0× its usual 19.8Naples, 20 December: 46.8 µg/m³, 2.4× its usual 19.4Naples, 21 December: 42.0 µg/m³Naples, 22 December: 15.8 µg/m³Naples, 23 December: 20.0 µg/m³Naples, 24 December: 13.3 µg/m³HolbocaHolboca, 13 December: 18.2 µg/m³Holboca, 14 December: 14.4 µg/m³Holboca, 15 December: 7.8 µg/m³Holboca, 16 December: 10.2 µg/m³Holboca, 17 December: 16.1 µg/m³Holboca, 18 December: 27.4 µg/m³Holboca, 19 December: 33.2 µg/m³, 2.2× its usual 14.9Holboca, 20 December: 44.2 µg/m³, 2.9× its usual 15.1Holboca, 21 December: 30.6 µg/m³, 2.0× its usual 15.3Holboca, 22 December: 18.3 µg/m³Holboca, 23 December: 8.4 µg/m³Holboca, 24 December: 14.6 µg/m³NyíregyházaNyíregyháza, 13 December: 22.6 µg/m³Nyíregyháza, 14 December: 14.7 µg/m³Nyíregyháza, 15 December: 12.5 µg/m³Nyíregyháza, 16 December: 23.1 µg/m³Nyíregyháza, 17 December: 28.5 µg/m³Nyíregyháza, 18 December: 33.4 µg/m³Nyíregyháza, 19 December: 43.0 µg/m³, 2.3× its usual 18.4Nyíregyháza, 20 December: 29.3 µg/m³Nyíregyháza, 21 December: 14.4 µg/m³Nyíregyháza, 22 December: 8.0 µg/m³Nyíregyháza, 23 December: 4.9 µg/m³Nyíregyháza, 24 December: 7.6 µg/m³EsztergomEsztergom, 13 December: 14.7 µg/m³Esztergom, 14 December: 18.1 µg/m³Esztergom, 15 December: 17.4 µg/m³Esztergom, 16 December: 18.6 µg/m³Esztergom, 17 December: 23.2 µg/m³Esztergom, 18 December: 26.5 µg/m³Esztergom, 19 December: 38.3 µg/m³, 2.4× its usual 16.0Esztergom, 20 December: 25.8 µg/m³Esztergom, 21 December: 11.3 µg/m³Esztergom, 22 December: 7.4 µg/m³Esztergom, 23 December: 5.4 µg/m³Esztergom, 24 December: 6.2 µg/m³PartizánskePartizánske, 13 December: 12.9 µg/m³Partizánske, 14 December: 25.5 µg/m³Partizánske, 15 December: 13.4 µg/m³Partizánske, 16 December: 27.7 µg/m³Partizánske, 17 December: 24.6 µg/m³Partizánske, 18 December: 19.0 µg/m³Partizánske, 19 December: 32.3 µg/m³, 2.1× its usual 15.2Partizánske, 20 December: 36.4 µg/m³, 2.4× its usual 15.3Partizánske, 21 December: 6.4 µg/m³Partizánske, 22 December: 5.4 µg/m³Partizánske, 23 December: 4.6 µg/m³Partizánske, 24 December: 10.7 µg/m³KlosterneuburgKlosterneuburg, 13 December: 25.3 µg/m³Klosterneuburg, 14 December: 11.8 µg/m³Klosterneuburg, 15 December: 7.3 µg/m³Klosterneuburg, 16 December: 13.0 µg/m³Klosterneuburg, 17 December: 9.1 µg/m³Klosterneuburg, 18 December: 12.8 µg/m³Klosterneuburg, 19 December: 34.1 µg/m³, 2.5× its usual 13.7Klosterneuburg, 20 December: 12.4 µg/m³Klosterneuburg, 21 December: 1.1 µg/m³Klosterneuburg, 22 December: 1.5 µg/m³Klosterneuburg, 23 December: 2.6 µg/m³Klosterneuburg, 24 December: 1.0 µg/m³BrnoBrno, 13 December: 15.3 µg/m³Brno, 14 December: 14.8 µg/m³Brno, 15 December: 10.6 µg/m³Brno, 16 December: 11.8 µg/m³Brno, 17 December: 16.7 µg/m³Brno, 18 December: 26.3 µg/m³Brno, 19 December: 33.7 µg/m³, 2.3× its usual 14.5Brno, 20 December: 24.2 µg/m³Brno, 21 December: 3.7 µg/m³Brno, 22 December: 3.5 µg/m³Brno, 23 December: 5.5 µg/m³Brno, 24 December: 6.4 µg/m³Vranov nad TopľouVranov nad Topľou, 13 December: 20.0 µg/m³Vranov nad Topľou, 14 December: 14.3 µg/m³Vranov nad Topľou, 15 December: 11.0 µg/m³Vranov nad Topľou, 16 December: 17.9 µg/m³Vranov nad Topľou, 17 December: 26.4 µg/m³Vranov nad Topľou, 18 December: 16.8 µg/m³Vranov nad Topľou, 19 December: 32.9 µg/m³, 2.1× its usual 15.9Vranov nad Topľou, 20 December: 24.0 µg/m³Vranov nad Topľou, 21 December: 11.1 µg/m³Vranov nad Topľou, 22 December: 7.2 µg/m³Vranov nad Topľou, 23 December: 6.7 µg/m³Vranov nad Topľou, 24 December: 11.1 µg/m³Hainburg an der Don…Hainburg an der Donau, 13 December: 13.9 µg/m³Hainburg an der Donau, 14 December: 12.6 µg/m³Hainburg an der Donau, 15 December: 8.3 µg/m³Hainburg an der Donau, 16 December: 12.7 µg/m³Hainburg an der Donau, 17 December: 11.4 µg/m³Hainburg an der Donau, 18 December: 25.1 µg/m³Hainburg an der Donau, 19 December: 30.3 µg/m³, 2.1× its usual 14.7Hainburg an der Donau, 20 December: 12.9 µg/m³Hainburg an der Donau, 21 December: 5.6 µg/m³Hainburg an der Donau, 22 December: 1.9 µg/m³Hainburg an der Donau, 23 December: 2.4 µg/m³Hainburg an der Donau, 24 December: 1.6 µg/m³MödlingMödling, 13 December: 22.1 µg/m³Mödling, 14 December: 7.4 µg/m³Mödling, 15 December: 7.2 µg/m³Mödling, 16 December: 9.7 µg/m³Mödling, 17 December: 15.6 µg/m³Mödling, 18 December: 23.2 µg/m³Mödling, 19 December: 30.2 µg/m³, 2.5× its usual 11.9Mödling, 20 December: 10.7 µg/m³Mödling, 21 December: 0.8 µg/m³Mödling, 22 December: 1.3 µg/m³Mödling, 23 December: 1.4 µg/m³Mödling, 24 December: 0.9 µg/m³ŽideniceŽidenice, 13 December: 10.4 µg/m³Židenice, 14 December: 15.3 µg/m³Židenice, 15 December: 10.4 µg/m³Židenice, 16 December: 17.1 µg/m³Židenice, 17 December: 13.7 µg/m³Židenice, 18 December: 22.2 µg/m³Židenice, 19 December: 29.5 µg/m³, 2.3× its usual 12.8Židenice, 20 December: 24.0 µg/m³Židenice, 21 December: no readingŽidenice, 22 December: no readingŽidenice, 23 December: 4.9 µg/m³Židenice, 24 December: no readingSlatinaSlatina, 13 December: 10.4 µg/m³Slatina, 14 December: 15.3 µg/m³Slatina, 15 December: 10.4 µg/m³Slatina, 16 December: 17.1 µg/m³Slatina, 17 December: 13.7 µg/m³Slatina, 18 December: 22.2 µg/m³Slatina, 19 December: 29.5 µg/m³, 2.3× its usual 12.8Slatina, 20 December: 24.0 µg/m³Slatina, 21 December: no readingSlatina, 22 December: no readingSlatina, 23 December: 4.9 µg/m³Slatina, 24 December: no readingSninaSnina, 13 December: 4.4 µg/m³Snina, 14 December: 6.5 µg/m³Snina, 15 December: 8.0 µg/m³Snina, 16 December: 14.4 µg/m³Snina, 17 December: 17.0 µg/m³Snina, 18 December: 16.1 µg/m³Snina, 19 December: 28.9 µg/m³, 2.9× its usual 9.9Snina, 20 December: 20.1 µg/m³Snina, 21 December: 7.9 µg/m³Snina, 22 December: 4.1 µg/m³Snina, 23 December: 3.2 µg/m³Snina, 24 December: 6.0 µg/m³WelsWels, 13 December: 7.3 µg/m³Wels, 14 December: 5.5 µg/m³Wels, 15 December: 7.3 µg/m³Wels, 16 December: 11.5 µg/m³Wels, 17 December: 13.8 µg/m³Wels, 18 December: 21.4 µg/m³Wels, 19 December: 28.5 µg/m³, 2.3× its usual 12.6Wels, 20 December: 7.3 µg/m³Wels, 21 December: 1.1 µg/m³Wels, 22 December: 0.9 µg/m³Wels, 23 December: 0.5 µg/m³Wels, 24 December: 1.5 µg/m³SenicaSenica, 13 December: 6.0 µg/m³Senica, 14 December: 15.2 µg/m³Senica, 15 December: 9.0 µg/m³Senica, 16 December: 17.4 µg/m³Senica, 17 December: 16.8 µg/m³Senica, 18 December: 19.5 µg/m³Senica, 19 December: 28.5 µg/m³, 2.1× its usual 13.4Senica, 20 December: 16.9 µg/m³Senica, 21 December: 1.6 µg/m³Senica, 22 December: 4.1 µg/m³Senica, 23 December: 3.7 µg/m³Senica, 24 December: 12.6 µg/m³SkopjeSkopje, 13 December: 73.6 µg/m³Skopje, 14 December: 50.8 µg/m³Skopje, 15 December: 14.2 µg/m³Skopje, 16 December: 10.7 µg/m³Skopje, 17 December: 28.7 µg/m³Skopje, 18 December: 66.4 µg/m³Skopje, 19 December: 88.2 µg/m³Skopje, 20 December: 103.0 µg/m³, 2.1× its usual 49.5Skopje, 21 December: 87.3 µg/m³Skopje, 22 December: 52.7 µg/m³Skopje, 23 December: 56.6 µg/m³Skopje, 24 December: 94.4 µg/m³CapannoriCapannori, 13 December: 17.3 µg/m³Capannori, 14 December: 31.1 µg/m³Capannori, 15 December: 35.0 µg/m³Capannori, 16 December: 17.6 µg/m³Capannori, 17 December: 47.8 µg/m³Capannori, 18 December: 90.8 µg/m³Capannori, 19 December: 123.0 µg/m³Capannori, 20 December: 74.3 µg/m³, 2.5× its usual 30.1Capannori, 21 December: 69.9 µg/m³Capannori, 22 December: 36.7 µg/m³Capannori, 23 December: 21.5 µg/m³Capannori, 24 December: 49.1 µg/m³GrazGraz, 13 December: 44.5 µg/m³Graz, 14 December: 31.0 µg/m³Graz, 15 December: 20.4 µg/m³Graz, 16 December: 24.2 µg/m³Graz, 17 December: 31.5 µg/m³Graz, 18 December: 38.1 µg/m³Graz, 19 December: 37.2 µg/m³Graz, 20 December: 45.2 µg/m³, 2.1× its usual 21.8Graz, 21 December: 44.4 µg/m³Graz, 22 December: 10.6 µg/m³Graz, 23 December: 5.2 µg/m³Graz, 24 December: 20.0 µg/m³PécsPécs, 13 December: 15.2 µg/m³Pécs, 14 December: 7.5 µg/m³Pécs, 15 December: 9.5 µg/m³Pécs, 16 December: 15.1 µg/m³Pécs, 17 December: 23.1 µg/m³Pécs, 18 December: 17.2 µg/m³Pécs, 19 December: 31.0 µg/m³Pécs, 20 December: 39.5 µg/m³, 2.4× its usual 16.4Pécs, 21 December: 22.9 µg/m³Pécs, 22 December: 7.1 µg/m³Pécs, 23 December: 3.4 µg/m³Pécs, 24 December: 11.7 µg/m³RuseRuse, 13 December: no readingRuse, 14 December: 30.4 µg/m³Ruse, 15 December: 8.9 µg/m³Ruse, 16 December: 9.6 µg/m³Ruse, 17 December: 15.6 µg/m³Ruse, 18 December: 12.6 µg/m³Ruse, 19 December: 32.4 µg/m³Ruse, 20 December: 36.8 µg/m³, 2.1× its usual 17.8Ruse, 21 December: 33.4 µg/m³Ruse, 22 December: 7.9 µg/m³Ruse, 23 December: 4.8 µg/m³Ruse, 24 December: 7.1 µg/m³VoitsbergVoitsberg, 13 December: 38.5 µg/m³Voitsberg, 14 December: 28.3 µg/m³Voitsberg, 15 December: 15.7 µg/m³Voitsberg, 16 December: 17.6 µg/m³Voitsberg, 17 December: 17.0 µg/m³Voitsberg, 18 December: 23.1 µg/m³Voitsberg, 19 December: 23.9 µg/m³Voitsberg, 20 December: 36.8 µg/m³, 2.1× its usual 17.5Voitsberg, 21 December: 23.1 µg/m³Voitsberg, 22 December: 6.4 µg/m³Voitsberg, 23 December: 4.9 µg/m³Voitsberg, 24 December: 16.0 µg/m³BucharestBucharest, 13 December: 20.6 µg/m³Bucharest, 14 December: 25.5 µg/m³Bucharest, 15 December: 8.8 µg/m³Bucharest, 16 December: 8.3 µg/m³Bucharest, 17 December: 14.9 µg/m³Bucharest, 18 December: 18.2 µg/m³Bucharest, 19 December: 28.1 µg/m³Bucharest, 20 December: 35.8 µg/m³, 2.2× its usual 16.2Bucharest, 21 December: 35.5 µg/m³, 2.2× its usual 16.3Bucharest, 22 December: 15.6 µg/m³Bucharest, 23 December: 3.7 µg/m³Bucharest, 24 December: 6.3 µg/m³SzegedSzeged, 13 December: no readingSzeged, 14 December: no readingSzeged, 15 December: no readingSzeged, 16 December: no readingSzeged, 17 December: no readingSzeged, 18 December: no readingSzeged, 19 December: no readingSzeged, 20 December: 34.7 µg/m³, 2.3× its usual 14.8Szeged, 21 December: 9.8 µg/m³Szeged, 22 December: 8.7 µg/m³Szeged, 23 December: 4.6 µg/m³Szeged, 24 December: 9.4 µg/m³AnconaAncona, 13 December: 8.6 µg/m³Ancona, 14 December: 37.4 µg/m³Ancona, 15 December: 31.0 µg/m³Ancona, 16 December: 5.4 µg/m³Ancona, 17 December: no readingAncona, 18 December: 22.5 µg/m³Ancona, 19 December: 18.2 µg/m³Ancona, 20 December: 33.0 µg/m³, 2.2× its usual 15.3Ancona, 21 December: 44.3 µg/m³Ancona, 22 December: 12.7 µg/m³Ancona, 23 December: 10.1 µg/m³Ancona, 24 December: 14.2 µg/m³13 Dec1517192123
The 60 cities with the highest readings of 66, 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
SarajevoFederation of B&H, Bosnia and Herzegovina3 230.020 December44.85.1×
PristinaPristina, Kosovo2 94.220 December20.44.6×
Banja LukaSrpska, Bosnia and Herzegovina3 190.019 December53.33.6×
BelgradeCentral Serbia, Serbia3 95.319 December27.63.5×
České BudějoviceSouth Bohemian Region, Czechia3 37.918 December10.93.5×
RužomberokŽilina Region, Slovakia1 58.819 December17.73.3×
HumennéPrešov Region, Slovakia2 54.919 December16.83.3×
BotevgradSofia, Bulgaria3 71.319 December22.23.2×
Novi SadVojvodina, Serbia3 68.719 December21.53.2×
CraiovaDolj, Romania2 49.919 December15.83.2×
PardubicePardubice Region, Czechia2 39.618 December12.23.2×
BaloteştiIlfov, Romania3 51.020 December16.23.1×
GyőrGyőr-Moson-Sopron, Hungary1 48.719 December15.93.1×
HandlováTrenčín Region, Slovakia3 41.418 December13.23.1×
Hradec KrálovéHradec Králové Region, Czechia2 40.319 December12.83.1×
NišCentral Serbia, Serbia3 120.520 December40.33.0×
BeneventoCampania, Italy2 65.820 December22.72.9×
HaskovoHaskovo, Bulgaria3 63.520 December21.82.9×
Moravská TřebováPardubice Region, Czechia2 53.119 December18.22.9×
HolbocaIași County, Romania3 44.220 December15.12.9×
SninaPrešov Region, Slovakia1 28.919 December9.92.9×
BitolaBitola, North Macedonia1 119.119 December43.32.8×
Banská BystricaBanská Bystrica Region, Slovakia2 46.919 December16.72.8×
IaşiIași County, Romania3 43.820 December16.52.7×
SalernoCampania, Italy2 27.719 December10.12.7×
CapannoriTuscany, Italy1 74.320 December30.12.5×
KlosterneuburgLower Austria, Austria1 34.119 December13.72.5×
MödlingLower Austria, Austria1 30.219 December11.92.5×
NaplesCampania, Italy2 46.820 December19.42.4×
PécsBaranya, Hungary1 39.520 December16.42.4×
PrievidzaTrenčín Region, Slovakia4 39.020 December16.22.4×
EsztergomKomárom-Esztergom, Hungary1 38.319 December16.02.4×
PartizánskeTrenčín Region, Slovakia2 36.420 December15.32.4×
LinzUpper Austria, Austria2 30.818 December12.92.4×
TetovoTetovo, North Macedonia1 154.019 December66.32.3×
ČaňaKošice Region, Slovakia1 50.916 December22.42.3×
NyíregyházaSzabolcs-Szatmár-Bereg, Hungary1 43.019 December18.42.3×
KošiceKošice Region, Slovakia1 41.317 December18.02.3×
SzegedCsongrád, Hungary1 34.720 December14.82.3×
BrnoSouth Moravian, Czechia1 33.719 December14.52.3×
Mladá BoleslavCentral Bohemia, Czechia2 33.518 December14.42.3×
BratislavaBratislava Region, Slovakia2 30.019 December13.02.3×
ŽideniceSouth Moravian, Czechia1 29.519 December12.82.3×
SlatinaSouth Moravian, Czechia1 29.519 December12.82.3×
WelsUpper Austria, Austria1 28.519 December12.62.3×
CasertaCampania, Italy1 28.319 December12.52.3×
Groß-EnzersdorfLower Austria, Austria1 27.719 December12.02.3×
MiskolcBorsod-Abaúj-Zemplén, Hungary1 55.717 December25.52.2×
Cluj-NapocaCluj County, Romania1 43.418 December19.62.2×
BucharestBucharest, Romania2 35.820 December16.22.2×
EisenstadtBurgenland, Austria2 34.819 December15.72.2×
AnconaThe Marches, Italy1 33.020 December15.32.2×
KolárovoNitra Region, Slovakia2 31.819 December14.72.2×
TrenčínTrenčín Region, Slovakia1 29.716 December13.72.2×
PerchtoldsdorfLower Austria, Austria1 26.219 December11.92.2×
SkopjeGrad Skopje, North Macedonia1 103.020 December49.52.1×
VelesVeles, North Macedonia1 95.819 December45.02.1×
GrazStyria, Austria1 45.220 December21.82.1×
RuseRuse, Bulgaria1 36.820 December17.82.1×
VoitsbergStyria, Austria1 36.820 December17.52.1×
Vranov nad TopľouPrešov Region, Slovakia1 32.919 December15.92.1×
Valašské MeziříčíZlín, Czechia1 30.616 December14.72.1×
Hainburg an der DonauLower Austria, Austria1 30.319 December14.72.1×
SenicaTrnava Region, Slovakia1 28.519 December13.42.1×
LitvínovÚstí nad Labem Region, Czechia1 25.118 December12.22.1×
ViennaVienna, Austria1 25.019 December12.02.1×

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 Slovakia and Austria

The largest of 10 episodes in Slovakia and Austria since our records began, by cities reached.

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

Use this page

SmogRank, Eastern Europe, December 2023: 66 cities with PM2.5 at twice their usual or more, 16 to 21 December 2023, smogrank.com/episodes/2023-12-eastern-europe (accessed 5 October 2026).

Download top 10 (PNG)

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.