SmogRank / Episodes / Slovakia
Eastern Europe, April 2026
For 2 days, from 16 to 17 April 2026, 24 cities in Slovakia, Hungary, Czechia and 5 more countries had PM2.5 at least twice their usual for the time of year. The worst reading was Szeged, Csongrád, Hungary: 43.9 µg/m³ on 16 April, about 4.9× its usual 8.9.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 24 in 8 countries
Days 2 16 to 17 April 2026
Worst day 16 April 22 cities counted
Furthest above usual 4.9× Szeged
Day by day
Play 16 April 22 cities at twice their usual or more
Budapest Gyál Dunaújváros Gyöngyös Veszprém Lučenec Zvolen Žiar nad Hronom Nitra Handlová Banská Bystrica Partizánske Prievidza Pécs Sereď Martin Trnava Trenčín Senec Liptovský Mikuláš Kazincbarcika Miskolc Pezinok Bratislava Čadca Kikinda Poprad Devínska Nová Ves Novi Sad Żywiec Třinec Hodonín Frýdek-Místek Český Těšín Bielsko-Biala Havířov Hranice Karviná Czechowice-Dziedzice Ostrava Přerov Bohumín Jastrzębie Zdrój Košice Eisenzicken Vienna Timişoara Nyíregyháza Wiener Neustadt Mödling Olomouc Klosterneuburg Racibórz Perchtoldsdorf Kraków Katowice Belgrade Židenice Brno Kędzierzyn-Koźle Ptuj Znojmo Tarnów Smederevo Travnik Jasło Maribor Sankt Pölten Snina Graz Dębica Krosno Žďár nad Sázavou Mielec Kłodzko Celje Jihlava Rzeszów Zalău Trbovlje Novo Mesto Pardubice Wolfsberg Amstetten Hradec Králové Nisko Przemyśl Jarosław Steyr Cluj-Napoca Ljubljana Klagenfurt am Wörthersee Kranj Ansfelden České Budějovice Linz Traun Târgu Jiu Dej Sighetu Marmaţiei Wels Mladá Boleslav Gorizia Beroun Koper Kladno Craiova Salzburg Freilassing Pilsen Saalfelden am Steinernen Meer Burghausen Piteşti Traunreut Codlea Sokolov Banja Luka Humenné Prešov Debrecen Trebišov Târgu Mureş Stodůlky Ružomberok Obrenovac Bardejov Vranov nad Topľou Žilina Komárno Esztergom Malacky Púchov Senica Baia Mare Zagreb Passau Győr Prague Říčany Szeged 13 Apr 14 15 16 17 18 19 20 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
Říčany Říčany, 13 April: 25.4 µg/m³, 3.0× usual Říčany, 14 April: 25.4 µg/m³, 3.0× usual Říčany, 15 April: 36.8 µg/m³, 4.3× usual Říčany, 16 April: 33.0 µg/m³, 3.8× usual Říčany, 17 April: 17.5 µg/m³, 2.0× usual Říčany, 18 April: 20.4 µg/m³, 2.4× usual Říčany, 19 April: 13.3 µg/m³, 1.5× usual Říčany, 20 April: 1.8 µg/m³, 0.2× usual Stodůlky Stodůlky, 13 April: 24.7 µg/m³, 2.0× usual Stodůlky, 14 April: 29.6 µg/m³, 2.4× usual Stodůlky, 15 April: 37.3 µg/m³, 3.1× usual Stodůlky, 16 April: 28.4 µg/m³, 2.3× usual Stodůlky, 17 April: 15.0 µg/m³, 1.2× usual Stodůlky, 18 April: 20.5 µg/m³, 1.7× usual Stodůlky, 19 April: 11.5 µg/m³, 1.0× usual Stodůlky, 20 April: 0.5 µg/m³, 0.0× usual Banja Luka Banja Luka, 13 April: 18.6 µg/m³, 1.4× usual Banja Luka, 14 April: 28.1 µg/m³, 2.1× usual Banja Luka, 15 April: no reading Banja Luka, 16 April: no reading Banja Luka, 17 April: 26.7 µg/m³, 2.0× usual Banja Luka, 18 April: 19.3 µg/m³, 1.5× usual Banja Luka, 19 April: 14.6 µg/m³, 1.1× usual Banja Luka, 20 April: 9.1 µg/m³, 0.7× usual Zagreb Zagreb, 13 April: 18.7 µg/m³, 1.5× usual Zagreb, 14 April: 27.0 µg/m³, 2.2× usual Zagreb, 15 April: 39.5 µg/m³, 3.2× usual Zagreb, 16 April: 37.8 µg/m³, 3.0× usual Zagreb, 17 April: 23.4 µg/m³, 1.9× usual Zagreb, 18 April: 19.0 µg/m³, 1.5× usual Zagreb, 19 April: 17.2 µg/m³, 1.4× usual Zagreb, 20 April: 11.3 µg/m³, 0.9× usual Púchov Púchov, 13 April: 15.7 µg/m³, 1.3× usual Púchov, 14 April: 16.9 µg/m³, 1.4× usual Púchov, 15 April: 33.9 µg/m³, 2.8× usual Púchov, 16 April: 35.6 µg/m³, 2.9× usual Púchov, 17 April: 24.1 µg/m³, 2.0× usual Púchov, 18 April: 17.7 µg/m³, 1.5× usual Púchov, 19 April: 19.4 µg/m³, 1.6× usual Púchov, 20 April: 13.6 µg/m³, 1.1× usual Szeged Szeged, 13 April: 12.5 µg/m³, 1.4× usual Szeged, 14 April: 10.7 µg/m³, 1.2× usual Szeged, 15 April: 10.3 µg/m³, 1.2× usual Szeged, 16 April: 43.9 µg/m³, 4.9× usual Szeged, 17 April: 14.0 µg/m³, 1.6× usual Szeged, 18 April: 9.2 µg/m³, 1.0× usual Szeged, 19 April: 7.4 µg/m³, 0.8× usual Szeged, 20 April: 6.5 µg/m³, 0.7× usual Obrenovac Obrenovac, 13 April: 16.1 µg/m³, 1.1× usual Obrenovac, 14 April: 13.7 µg/m³, 0.9× usual Obrenovac, 15 April: 19.2 µg/m³, 1.3× usual Obrenovac, 16 April: 32.9 µg/m³, 2.3× usual Obrenovac, 17 April: 31.2 µg/m³, 2.2× usual Obrenovac, 18 April: 26.5 µg/m³, 1.8× usual Obrenovac, 19 April: 20.4 µg/m³, 1.4× usual Obrenovac, 20 April: 18.1 µg/m³, 1.2× usual Prague Prague, 13 April: 16.7 µg/m³, 1.7× usual Prague, 14 April: 21.8 µg/m³, 2.2× usual Prague, 15 April: no reading Prague, 16 April: 32.8 µg/m³, 3.3× usual Prague, 17 April: no reading Prague, 18 April: 15.2 µg/m³, 1.6× usual Prague, 19 April: 11.8 µg/m³, 1.2× usual Prague, 20 April: 3.5 µg/m³, 0.4× usual Baia Mare Baia Mare, 13 April: 11.8 µg/m³, 1.1× usual Baia Mare, 14 April: 10.2 µg/m³, 0.9× usual Baia Mare, 15 April: no reading Baia Mare, 16 April: 32.4 µg/m³, 2.9× usual Baia Mare, 17 April: 24.5 µg/m³, 2.2× usual Baia Mare, 18 April: 15.3 µg/m³, 1.4× usual Baia Mare, 19 April: 15.6 µg/m³, 1.4× usual Baia Mare, 20 April: 24.2 µg/m³, 2.2× usual Prešov Prešov, 13 April: 14.3 µg/m³, 1.0× usual Prešov, 14 April: 21.1 µg/m³, 1.5× usual Prešov, 15 April: 18.9 µg/m³, 1.3× usual Prešov, 16 April: 30.5 µg/m³, 2.1× usual Prešov, 17 April: 23.9 µg/m³, 1.6× usual Prešov, 18 April: 10.7 µg/m³, 0.7× usual Prešov, 19 April: 14.7 µg/m³, 1.0× usual Prešov, 20 April: 9.8 µg/m³, 0.7× usual Žilina Žilina, 13 April: 12.5 µg/m³, 1.1× usual Žilina, 14 April: 14.7 µg/m³, 1.3× usual Žilina, 15 April: 24.7 µg/m³, 2.1× usual Žilina, 16 April: 29.7 µg/m³, 2.6× usual Žilina, 17 April: 13.7 µg/m³, 1.2× usual Žilina, 18 April: 15.1 µg/m³, 1.3× usual Žilina, 19 April: 13.9 µg/m³, 1.2× usual Žilina, 20 April: 4.3 µg/m³, 0.4× usual Győr Győr, 13 April: 13.6 µg/m³, 1.5× usual Győr, 14 April: 16.8 µg/m³, 1.8× usual Győr, 15 April: 21.6 µg/m³, 2.3× usual Győr, 16 April: 28.9 µg/m³, 3.1× usual Győr, 17 April: 24.0 µg/m³, 2.6× usual Győr, 18 April: 11.9 µg/m³, 1.3× usual Győr, 19 April: 11.4 µg/m³, 1.2× usual Győr, 20 April: 7.9 µg/m³, 0.9× usual Vranov nad Topľou Vranov nad Topľou, 13 April: 10.7 µg/m³, 0.9× usual Vranov nad Topľou, 14 April: 14.5 µg/m³, 1.3× usual Vranov nad Topľou, 15 April: 15.6 µg/m³, 1.4× usual Vranov nad Topľou, 16 April: 28.7 µg/m³, 2.5× usual Vranov nad Topľou, 17 April: 20.3 µg/m³, 1.8× usual Vranov nad Topľou, 18 April: 8.6 µg/m³, 0.8× usual Vranov nad Topľou, 19 April: 12.2 µg/m³, 1.1× usual Vranov nad Topľou, 20 April: 8.0 µg/m³, 0.7× usual Senica Senica, 13 April: 11.5 µg/m³, 1.2× usual Senica, 14 April: 12.5 µg/m³, 1.3× usual Senica, 15 April: 24.5 µg/m³, 2.5× usual Senica, 16 April: 28.4 µg/m³, 2.9× usual Senica, 17 April: 17.4 µg/m³, 1.8× usual Senica, 18 April: 13.5 µg/m³, 1.4× usual Senica, 19 April: 15.0 µg/m³, 1.5× usual Senica, 20 April: no reading Debrecen Debrecen, 13 April: 20.1 µg/m³, 1.5× usual Debrecen, 14 April: 15.1 µg/m³, 1.1× usual Debrecen, 15 April: 24.1 µg/m³, 1.8× usual Debrecen, 16 April: 28.1 µg/m³, 2.1× usual Debrecen, 17 April: 27.6 µg/m³, 2.0× usual Debrecen, 18 April: 9.5 µg/m³, 0.7× usual Debrecen, 19 April: 12.2 µg/m³, 0.9× usual Debrecen, 20 April: 10.5 µg/m³, 0.8× usual Komárno Komárno, 13 April: 12.0 µg/m³, 1.2× usual Komárno, 14 April: 10.5 µg/m³, 1.0× usual Komárno, 15 April: 18.6 µg/m³, 1.8× usual Komárno, 16 April: 27.3 µg/m³, 2.7× usual Komárno, 17 April: 20.3 µg/m³, 2.0× usual Komárno, 18 April: 12.8 µg/m³, 1.3× usual Komárno, 19 April: 14.3 µg/m³, 1.4× usual Komárno, 20 April: 6.5 µg/m³, 0.6× usual Humenné Humenné, 13 April: 11.8 µg/m³, 0.9× usual Humenné, 14 April: 17.0 µg/m³, 1.3× usual Humenné, 15 April: 17.9 µg/m³, 1.4× usual Humenné, 16 April: 26.1 µg/m³, 2.0× usual Humenné, 17 April: 21.8 µg/m³, 1.7× usual Humenné, 18 April: 10.7 µg/m³, 0.8× usual Humenné, 19 April: 14.1 µg/m³, 1.1× usual Humenné, 20 April: 8.6 µg/m³, 0.7× usual Esztergom Esztergom, 13 April: 12.6 µg/m³, 1.3× usual Esztergom, 14 April: 13.0 µg/m³, 1.3× usual Esztergom, 15 April: 17.0 µg/m³, 1.8× usual Esztergom, 16 April: 26.0 µg/m³, 2.7× usual Esztergom, 17 April: 17.8 µg/m³, 1.8× usual Esztergom, 18 April: 11.5 µg/m³, 1.2× usual Esztergom, 19 April: 16.1 µg/m³, 1.7× usual Esztergom, 20 April: 9.4 µg/m³, 1.0× usual Bardejov Bardejov, 13 April: 9.5 µg/m³, 0.9× usual Bardejov, 14 April: 14.1 µg/m³, 1.3× usual Bardejov, 15 April: 15.0 µg/m³, 1.4× usual Bardejov, 16 April: 25.8 µg/m³, 2.3× usual Bardejov, 17 April: 21.1 µg/m³, 1.9× usual Bardejov, 18 April: 14.4 µg/m³, 1.3× usual Bardejov, 19 April: 11.3 µg/m³, 1.0× usual Bardejov, 20 April: 9.6 µg/m³, 0.9× usual Trebišov Trebišov, 13 April: 11.5 µg/m³, 1.0× usual Trebišov, 14 April: 14.6 µg/m³, 1.2× usual Trebišov, 15 April: 16.5 µg/m³, 1.4× usual Trebišov, 16 April: 25.8 µg/m³, 2.2× usual Trebišov, 17 April: 21.7 µg/m³, 1.9× usual Trebišov, 18 April: 9.5 µg/m³, 0.8× usual Trebišov, 19 April: 12.9 µg/m³, 1.1× usual Trebišov, 20 April: 8.7 µg/m³, 0.7× usual Ružomberok Ružomberok, 13 April: 14.0 µg/m³, 1.3× usual Ružomberok, 14 April: 14.2 µg/m³, 1.3× usual Ružomberok, 15 April: 17.5 µg/m³, 1.6× usual Ružomberok, 16 April: 25.7 µg/m³, 2.3× usual Ružomberok, 17 April: 20.5 µg/m³, 1.8× usual Ružomberok, 18 April: 12.9 µg/m³, 1.2× usual Ružomberok, 19 April: 16.5 µg/m³, 1.5× usual Ružomberok, 20 April: 12.6 µg/m³, 1.1× usual Passau Passau, 13 April: 17.8 µg/m³, 2.1× usual Passau, 14 April: 22.9 µg/m³, 2.8× usual Passau, 15 April: 21.9 µg/m³, 2.6× usual Passau, 16 April: 25.2 µg/m³, 3.0× usual Passau, 17 April: 16.0 µg/m³, 1.9× usual Passau, 18 April: 13.1 µg/m³, 1.6× usual Passau, 19 April: 13.3 µg/m³, 1.6× usual Passau, 20 April: 6.8 µg/m³, 0.8× usual Malacky Malacky, 13 April: 14.7 µg/m³, 1.6× usual Malacky, 14 April: 13.2 µg/m³, 1.5× usual Malacky, 15 April: 22.5 µg/m³, 2.5× usual Malacky, 16 April: 25.0 µg/m³, 2.8× usual Malacky, 17 April: 17.6 µg/m³, 2.0× usual Malacky, 18 April: 11.1 µg/m³, 1.2× usual Malacky, 19 April: 13.1 µg/m³, 1.5× usual Malacky, 20 April: 5.1 µg/m³, 0.6× usual Târgu Mureş Târgu Mureş, 13 April: 27.2 µg/m³, 1.6× usual Târgu Mureş, 14 April: 9.4 µg/m³, 0.5× usual Târgu Mureş, 15 April: 25.8 µg/m³, 1.5× usual Târgu Mureş, 16 April: 26.8 µg/m³, 1.5× usual Târgu Mureş, 17 April: 39.6 µg/m³, 2.3× usual Târgu Mureş, 18 April: 20.6 µg/m³, 1.2× usual Târgu Mureş, 19 April: 18.3 µg/m³, 1.0× usual Târgu Mureş, 20 April: 24.5 µg/m³, 1.4× usual 13 Apr 14 15 16 17 18 19 20 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. Good 0–50
Moderate 51–100
Sensitive groups 101–150
Unhealthy 151–200
Very unhealthy 201–300
Hazardous 301+
Every city it reached
City Days Highest Usual Above usual
Szeged Csongrád, Hungary 1 16 April 8.9 4.9× Říčany Central Bohemia, Czechia 1 15 April 8.6 4.3× Prague Prague, Czechia 1 16 April 9.8 3.3× Zagreb Zagreb, Croatia 1 15 April 12.5 3.2× Győr Győr-Moson-Sopron, Hungary 1 16 April 9.2 3.1× Stodůlky Prague, Czechia 1 15 April 12.1 3.1× Passau Bavaria, Germany 1 16 April 8.3 3.0× Púchov Trenčín Region, Slovakia 1 16 April 12.2 2.9× Baia Mare Maramureş, Romania 1 16 April 11.2 2.9× Senica Trnava Region, Slovakia 1 16 April 9.9 2.9× Malacky Bratislava Region, Slovakia 1 16 April 9.0 2.8× Esztergom Komárom-Esztergom, Hungary 1 16 April 9.7 2.7× Komárno Nitra Region, Slovakia 1 16 April 10.2 2.7× Žilina Žilina Region, Slovakia 1 16 April 11.5 2.6× Vranov nad Topľou Prešov Region, Slovakia 1 16 April 11.3 2.5× Bardejov Prešov Region, Slovakia 1 16 April 11.1 2.3× Ružomberok Žilina Region, Slovakia 1 16 April 11.2 2.3× Obrenovac Central Serbia, Serbia 2 16 April 14.5 2.3× Târgu Mureş Mureș County, Romania 1 17 April 17.5 2.3× Trebišov Košice Region, Slovakia 1 16 April 11.7 2.2× Banja Luka Srpska, Bosnia and Herzegovina 1 14 April 13.3 2.1× Prešov Prešov Region, Slovakia 1 16 April 14.5 2.1× Debrecen Hajdú-Bihar, Hungary 2 16 April 13.6 2.1× Humenné Prešov Region, Slovakia 1 16 April 12.8 2.0×
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 Slovakia and Hungary
Number 2 of 8 episodes in Slovakia and Hungary since our records began, by cities reached.
Eastern Europe, December 2023 29 Eastern Europe, April 2026 24 Germany, Slovakia and 2 more countries, June 2023 19 Slovakia, Czechia and Poland, June 2026 16 Czechia, Slovakia and Austria, December 2023 16 South-eastern Europe, December 2023 16 Eastern Europe, June 2026 14 Czechia and Slovakia, January 2023 9 Bars: cities reached; colour: the level of the episode's highest daily reading.
Use this page SmogRank, Eastern Europe, April 2026: 24 cities with PM2.5 at twice their usual or more, 16 to 17 April 2026, smogrank.com/episodes/2026-04-eastern-europe (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.
