SmogRank / Episodes / Belgium
Belgium and Germany, May 2023
For 1 day, on 22 May 2023, 26 cities in Belgium, Germany, The Netherlands and 1 more countries had PM2.5 at least twice their usual for the time of year. The worst reading was Andenne, Wallonia, Belgium: 38.1 µg/m³ on 22 May, about 7.5× its usual 5.1.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 26 in 4 countries
Days 1 22 May 2023
Worst day 22 May 26 cities counted
Furthest above usual 7.5× Andenne
Day by day
Play 22 May 26 cities at twice their usual or more
Flémalle-Haute Esch-sur-Alzette Luxembourg Verdun Eindhoven Trier Mönchengladbach Tilburg Venray Metz Willebroek Kapellen Breda Zwijndrecht Krefeld Stabroek Beveren Nijmegen Leverkusen Ratingen Duisburg Saint-Dizier Nancy Reims IJsselstein Forbach Ridderkerk Oberhausen Utrecht Lochristi Barneveld Saarbrücken Maarssen Rotterdam Essen Wuppertal Gent Épernay Lunéville Gelsenkirchen Hattingen Maassluis Borken Denain Waregem The Hague 's-Gravenzande Badhoevedorp Amsterdam Hillegom Maldegem Saint-Quentin Hagen Zaanstad Purmerend Kortrijk Velserbroek Datteln Velsen-Zuid Dortmund Lüdenscheid Roubaix Izegem Schwerte Enschede Douai Menen Bad Kreuznach Troyes Kaiserslautern Roeselare Lille Unna Limburg an der Lahn Netphen Münster Wiesbaden Mainz Coulommiers Béthune Lingen Kehl Soest Worms Rüsselsheim am Main Koksijde Lampertheim Ludwigshafen am Rhein Warstein Mannheim Eschborn Speyer Baden-Baden Eggenstein-Leopoldshafen Creil Karlsruhe Bensheim Darmstadt Dunkirk Frankfurt am Main Gießen Amiens Osnabrück Freiburg Melun Heidelberg Marburg an der Lahn Fontainebleau Sarcelles Wiesloch Domont Paris Beauvais Pforzheim Bielefeld Marsberg Sainte-Geneviève-des-Bois Großostheim Aschaffenburg Calais Villingen-Schwenningen Herrenberg Étampes Heilbronn Ludwigsburg Tübingen Stuttgart Rambouillet Rinteln Filderstadt Reutlingen Kassel Fulda Lauda-Königshofen Olivet Chartres Dreux Dieppe Rouen Würzburg Canterbury Évreux Clacton-on-Sea Göttingen Hannover Norwich Aalen Biberach an der Riß Hildesheim Eisenach Ulm Neu-Ulm Meiningen Mühlhausen Canvey Island Gillingham Goslar Ansbach Salzgitter Grays Lisieux Seaford Braunschweig Bamberg Le Havre Newmarket Nordhausen Dagenham Coburg Erfurt Brighton Nuremberg Alençon London Augsburg Le Mans Halberstadt Weimar Saalfeld Caen Biggleswade Hayes Starnberg Munich Evergem Solingen Thionville Antwerp Bergheim Düsseldorf Mol Jüchen Brussels Jülich Köln Grimbergen Aachen Bonn Mons Neuwied Aarschot Tournai Marche-en-Famenne Koblenz Bendorf Heerlen Charleroi Liège Eupen Andenne 19 May 20 21 22 23 24 25 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
Andenne Andenne, 19 May: 13.4 µg/m³, 2.6× usual Andenne, 20 May: 11.9 µg/m³, 2.3× usual Andenne, 21 May: 15.9 µg/m³, 3.1× usual Andenne, 22 May: 38.1 µg/m³, 7.5× usual Andenne, 23 May: 15.7 µg/m³, 3.1× usual Andenne, 24 May: 6.2 µg/m³, 1.2× usual Andenne, 25 May: 10.6 µg/m³, 2.1× usual Koblenz Koblenz, 19 May: 5.7 µg/m³, 0.8× usual Koblenz, 20 May: 10.2 µg/m³, 1.4× usual Koblenz, 21 May: 19.3 µg/m³, 2.7× usual Koblenz, 22 May: 38.1 µg/m³, 5.3× usual Koblenz, 23 May: 13.9 µg/m³, 1.9× usual Koblenz, 24 May: 7.1 µg/m³, 1.0× usual Koblenz, 25 May: 7.5 µg/m³, 1.0× usual Aarschot Aarschot, 19 May: 10.0 µg/m³, 1.4× usual Aarschot, 20 May: 7.7 µg/m³, 1.0× usual Aarschot, 21 May: 13.3 µg/m³, 1.8× usual Aarschot, 22 May: 32.5 µg/m³, 4.4× usual Aarschot, 23 May: 12.2 µg/m³, 1.6× usual Aarschot, 24 May: 10.0 µg/m³, 1.4× usual Aarschot, 25 May: 10.1 µg/m³, 1.4× usual Grimbergen Grimbergen, 19 May: 10.3 µg/m³, 1.2× usual Grimbergen, 20 May: 7.5 µg/m³, 0.9× usual Grimbergen, 21 May: 11.9 µg/m³, 1.4× usual Grimbergen, 22 May: 31.7 µg/m³, 3.8× usual Grimbergen, 23 May: 13.4 µg/m³, 1.6× usual Grimbergen, 24 May: 9.9 µg/m³, 1.2× usual Grimbergen, 25 May: 9.0 µg/m³, 1.1× usual Liège Liège, 19 May: 8.0 µg/m³, 1.5× usual Liège, 20 May: 6.6 µg/m³, 1.2× usual Liège, 21 May: 15.9 µg/m³, 2.9× usual Liège, 22 May: 31.3 µg/m³, 5.7× usual Liège, 23 May: 13.4 µg/m³, 2.4× usual Liège, 24 May: 7.9 µg/m³, 1.4× usual Liège, 25 May: 11.2 µg/m³, 2.0× usual Bendorf Bendorf, 19 May: 5.6 µg/m³, 1.0× usual Bendorf, 20 May: 11.3 µg/m³, 2.0× usual Bendorf, 21 May: 18.0 µg/m³, 3.2× usual Bendorf, 22 May: 30.0 µg/m³, 5.4× usual Bendorf, 23 May: 12.6 µg/m³, 2.3× usual Bendorf, 24 May: 5.7 µg/m³, 1.0× usual Bendorf, 25 May: 7.6 µg/m³, 1.4× usual Bergheim Bergheim, 19 May: 7.2 µg/m³, 0.7× usual Bergheim, 20 May: 7.4 µg/m³, 0.8× usual Bergheim, 21 May: 15.6 µg/m³, 1.6× usual Bergheim, 22 May: 30.0 µg/m³, 3.1× usual Bergheim, 23 May: 9.0 µg/m³, 0.9× usual Bergheim, 24 May: 9.2 µg/m³, 0.9× usual Bergheim, 25 May: 12.5 µg/m³, 1.3× usual Charleroi Charleroi, 19 May: 8.9 µg/m³, 1.6× usual Charleroi, 20 May: 7.4 µg/m³, 1.4× usual Charleroi, 21 May: 12.9 µg/m³, 2.4× usual Charleroi, 22 May: 29.8 µg/m³, 5.5× usual Charleroi, 23 May: 14.1 µg/m³, 2.6× usual Charleroi, 24 May: 7.2 µg/m³, 1.3× usual Charleroi, 25 May: 10.4 µg/m³, 1.9× usual Eupen Eupen, 19 May: 4.9 µg/m³, 1.0× usual Eupen, 20 May: 6.6 µg/m³, 1.3× usual Eupen, 21 May: 16.4 µg/m³, 3.3× usual Eupen, 22 May: 29.7 µg/m³, 5.9× usual Eupen, 23 May: 13.8 µg/m³, 2.8× usual Eupen, 24 May: 6.1 µg/m³, 1.2× usual Eupen, 25 May: 14.5 µg/m³, 2.9× usual Bonn Bonn, 19 May: 5.6 µg/m³, 0.8× usual Bonn, 20 May: 6.9 µg/m³, 1.0× usual Bonn, 21 May: 14.5 µg/m³, 2.0× usual Bonn, 22 May: 29.6 µg/m³, 4.1× usual Bonn, 23 May: 11.3 µg/m³, 1.6× usual Bonn, 24 May: 9.4 µg/m³, 1.3× usual Bonn, 25 May: 10.6 µg/m³, 1.5× usual Neuwied Neuwied, 19 May: 5.2 µg/m³, 0.8× usual Neuwied, 20 May: 10.3 µg/m³, 1.5× usual Neuwied, 21 May: 17.1 µg/m³, 2.5× usual Neuwied, 22 May: 29.0 µg/m³, 4.3× usual Neuwied, 23 May: 13.9 µg/m³, 2.0× usual Neuwied, 24 May: 6.5 µg/m³, 1.0× usual Neuwied, 25 May: 7.3 µg/m³, 1.1× usual Köln Köln, 19 May: 6.0 µg/m³, 0.8× usual Köln, 20 May: 6.6 µg/m³, 0.9× usual Köln, 21 May: 16.1 µg/m³, 2.1× usual Köln, 22 May: 29.0 µg/m³, 3.8× usual Köln, 23 May: 11.4 µg/m³, 1.5× usual Köln, 24 May: 10.2 µg/m³, 1.3× usual Köln, 25 May: 11.9 µg/m³, 1.5× usual Jülich Jülich, 19 May: 10.1 µg/m³, 1.3× usual Jülich, 20 May: 9.9 µg/m³, 1.3× usual Jülich, 21 May: 16.8 µg/m³, 2.2× usual Jülich, 22 May: 28.7 µg/m³, 3.7× usual Jülich, 23 May: 11.2 µg/m³, 1.4× usual Jülich, 24 May: 7.6 µg/m³, 1.0× usual Jülich, 25 May: 11.6 µg/m³, 1.5× usual Aachen Aachen, 19 May: 8.3 µg/m³, 1.2× usual Aachen, 20 May: 8.5 µg/m³, 1.2× usual Aachen, 21 May: 19.2 µg/m³, 2.7× usual Aachen, 22 May: 28.4 µg/m³, 4.0× usual Aachen, 23 May: 13.3 µg/m³, 1.9× usual Aachen, 24 May: 9.1 µg/m³, 1.3× usual Aachen, 25 May: 14.5 µg/m³, 2.0× usual Heerlen Heerlen, 19 May: no reading Heerlen, 20 May: 6.9 µg/m³, 1.3× usual Heerlen, 21 May: 12.6 µg/m³, 2.4× usual Heerlen, 22 May: 28.0 µg/m³, 5.4× usual Heerlen, 23 May: no reading Heerlen, 24 May: no reading Heerlen, 25 May: 8.6 µg/m³, 1.7× usual Mons Mons, 19 May: 10.9 µg/m³, 1.7× usual Mons, 20 May: 8.1 µg/m³, 1.2× usual Mons, 21 May: 12.9 µg/m³, 2.0× usual Mons, 22 May: 28.0 µg/m³, 4.2× usual Mons, 23 May: 12.2 µg/m³, 1.8× usual Mons, 24 May: 6.8 µg/m³, 1.0× usual Mons, 25 May: 8.5 µg/m³, 1.3× usual Antwerp Antwerp, 19 May: 10.8 µg/m³, 1.2× usual Antwerp, 20 May: 9.0 µg/m³, 1.0× usual Antwerp, 21 May: 12.4 µg/m³, 1.4× usual Antwerp, 22 May: 26.7 µg/m³, 3.0× usual Antwerp, 23 May: 12.9 µg/m³, 1.4× usual Antwerp, 24 May: 9.9 µg/m³, 1.1× usual Antwerp, 25 May: 10.4 µg/m³, 1.2× usual Mol Mol, 19 May: 9.8 µg/m³, 1.2× usual Mol, 20 May: 7.2 µg/m³, 0.8× usual Mol, 21 May: 12.7 µg/m³, 1.5× usual Mol, 22 May: 26.6 µg/m³, 3.1× usual Mol, 23 May: 10.7 µg/m³, 1.3× usual Mol, 24 May: 9.1 µg/m³, 1.1× usual Mol, 25 May: 9.5 µg/m³, 1.1× usual Jüchen Jüchen, 19 May: 9.4 µg/m³, 1.2× usual Jüchen, 20 May: 8.5 µg/m³, 1.1× usual Jüchen, 21 May: 14.7 µg/m³, 1.9× usual Jüchen, 22 May: 26.2 µg/m³, 3.4× usual Jüchen, 23 May: 8.2 µg/m³, 1.1× usual Jüchen, 24 May: 9.1 µg/m³, 1.2× usual Jüchen, 25 May: 14.8 µg/m³, 1.9× usual Solingen Solingen, 19 May: 6.4 µg/m³, 0.6× usual Solingen, 20 May: 7.7 µg/m³, 0.8× usual Solingen, 21 May: 15.9 µg/m³, 1.6× usual Solingen, 22 May: 25.9 µg/m³, 2.6× usual Solingen, 23 May: 12.2 µg/m³, 1.2× usual Solingen, 24 May: 11.5 µg/m³, 1.2× usual Solingen, 25 May: 13.3 µg/m³, 1.3× usual Brussels Brussels, 19 May: 10.8 µg/m³, 1.5× usual Brussels, 20 May: 9.3 µg/m³, 1.3× usual Brussels, 21 May: 11.9 µg/m³, 1.6× usual Brussels, 22 May: 25.6 µg/m³, 3.5× usual Brussels, 23 May: 10.4 µg/m³, 1.4× usual Brussels, 24 May: 7.6 µg/m³, 1.0× usual Brussels, 25 May: 8.4 µg/m³, 1.1× usual Düsseldorf Düsseldorf, 19 May: 10.0 µg/m³, 1.2× usual Düsseldorf, 20 May: 10.4 µg/m³, 1.3× usual Düsseldorf, 21 May: 16.8 µg/m³, 2.0× usual Düsseldorf, 22 May: 25.4 µg/m³, 3.1× usual Düsseldorf, 23 May: 9.6 µg/m³, 1.2× usual Düsseldorf, 24 May: 10.2 µg/m³, 1.2× usual Düsseldorf, 25 May: 12.4 µg/m³, 1.5× usual Thionville Thionville, 19 May: 11.6 µg/m³, 1.3× usual Thionville, 20 May: 10.8 µg/m³, 1.2× usual Thionville, 21 May: 17.3 µg/m³, 1.9× usual Thionville, 22 May: 25.3 µg/m³, 2.8× usual Thionville, 23 May: 17.8 µg/m³, 2.0× usual Thionville, 24 May: 11.9 µg/m³, 1.3× usual Thionville, 25 May: 11.7 µg/m³, 1.3× usual Evergem Evergem, 19 May: 14.9 µg/m³, 1.5× usual Evergem, 20 May: 12.0 µg/m³, 1.2× usual Evergem, 21 May: 13.9 µg/m³, 1.4× usual Evergem, 22 May: 25.1 µg/m³, 2.5× usual Evergem, 23 May: 13.4 µg/m³, 1.3× usual Evergem, 24 May: 9.1 µg/m³, 0.9× usual Evergem, 25 May: 12.3 µg/m³, 1.2× usual Marche-en-Famenne Marche-en-Famenne, 19 May: 5.1 µg/m³, 1.0× usual Marche-en-Famenne, 20 May: 5.8 µg/m³, 1.2× usual Marche-en-Famenne, 21 May: 17.4 µg/m³, 3.5× usual Marche-en-Famenne, 22 May: 25.0 µg/m³, 5.0× usual Marche-en-Famenne, 23 May: 12.5 µg/m³, 2.5× usual Marche-en-Famenne, 24 May: 4.2 µg/m³, 0.8× usual Marche-en-Famenne, 25 May: 10.8 µg/m³, 2.2× usual Tournai Tournai, 19 May: 13.6 µg/m³, 2.4× usual Tournai, 20 May: 8.5 µg/m³, 1.5× usual Tournai, 21 May: 15.7 µg/m³, 2.8× usual Tournai, 22 May: 25.0 µg/m³, 4.4× usual Tournai, 23 May: 9.7 µg/m³, 1.7× usual Tournai, 24 May: 6.6 µg/m³, 1.2× usual Tournai, 25 May: 9.2 µg/m³, 1.6× usual 19 May 20 21 22 23 24 25 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
Andenne Wallonia, Belgium 1 22 May 5.1 7.5× Eupen Wallonia, Belgium 1 22 May 4.1 5.9× Liège Wallonia, Belgium 1 22 May 5.5 5.7× Charleroi Wallonia, Belgium 1 22 May 5.4 5.5× Heerlen Limburg, The Netherlands 1 22 May 5.2 5.4× Bendorf Rheinland-Pfalz, Germany 1 22 May 5.6 5.4× Koblenz Rheinland-Pfalz, Germany 1 22 May 7.2 5.3× Marche-en-Famenne Wallonia, Belgium 1 22 May 4.2 5.0× Aarschot Flanders, Belgium 1 22 May 7.4 4.4× Tournai Wallonia, Belgium 1 22 May 5.7 4.4× Neuwied Rheinland-Pfalz, Germany 1 22 May 6.8 4.3× Mons Wallonia, Belgium 1 22 May 6.6 4.2× Bonn North Rhine-Westphalia, Germany 1 22 May 7.2 4.1× Aachen North Rhine-Westphalia, Germany 1 22 May 7.1 4.0× Grimbergen Flanders, Belgium 1 22 May 8.4 3.8× Köln North Rhine-Westphalia, Germany 1 22 May 7.7 3.8× Jülich North Rhine-Westphalia, Germany 1 22 May 7.8 3.7× Brussels Brussels Capital, Belgium 1 22 May 7.4 3.5× Jüchen North Rhine-Westphalia, Germany 1 22 May 7.7 3.4× Mol Flanders, Belgium 1 22 May 8.5 3.1× Bergheim North Rhine-Westphalia, Germany 1 22 May 9.8 3.1× Düsseldorf North Rhine-Westphalia, Germany 1 22 May 8.3 3.1× Antwerp Flanders, Belgium 1 22 May 9.0 3.0× Thionville Grand Est, France 1 22 May 9.0 2.8× Solingen North Rhine-Westphalia, Germany 1 22 May 10.0 2.6× Evergem Flanders, Belgium 1 22 May 10.0 2.5×
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 Belgium and Germany
Number 7 of 13 episodes in Belgium and Germany since our records began, by cities reached.
Central Europe, February 2023 604 Eastern Europe, December 2023 107 Central Europe, April 2023 65 France, Belgium and United Kingdom, November and December 2023 43 United Kingdom and Belgium, September 2023 42 France and Belgium, April 2023 36 Belgium and Germany, May 2023 26 Germany, Slovakia and 2 more countries, June 2023 19 Belgium and France, August 2023 15 United Kingdom, Belgium and France, June 2023 10 Flanders and Wallonia, Belgium, May 2023 10 Belgium and France, April 2023 9 Bars: cities reached; colour: the level of the episode's highest daily reading. All 13 .
Use this page SmogRank, Belgium and Germany, May 2023: 26 cities with PM2.5 at twice their usual or more, 22 May 2023, smogrank.com/episodes/2023-05-belgium-and-germany (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.
