SmogRank / Episodes / France
France and Belgium, April 2023
For 2 days, from 17 to 18 April 2023, 36 cities in France, Belgium and Germany had PM2.5 at least twice their usual for the time of year. The worst reading was Dreux, Centre-Val de Loire, France: 32.8 µg/m³ on 18 April, about 4.8× its usual 6.9.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 36 in 3 countries
Days 2 17 to 18 April 2023
Worst day 18 April 28 cities counted
Furthest above usual 5.4× Angers
Day by day
Play 18 April 28 cities at twice their usual or more
Coulommiers Melun Fontainebleau Épernay Reims Calais Koksijde Olivet Troyes Auxerre Lochristi Charleroi Blois Brussels Canterbury Bourges Willebroek Zwijndrecht Saint-Dizier Antwerp Stabroek Kapellen Clacton-on-Sea Aarschot Tours Seaford Joué-lès-Tours Verdun Canvey Island Grays Brighton Breda Mol Bexley Flémalle-Haute Dagenham Ridderkerk Dijon Tilburg London Esch-sur-Alzette Eindhoven Luxembourg Hayes Thionville Metz Eupen Nancy Heerlen Aachen Portsmouth Venray Vesoul Reading Nijmegen Jülich Trier Besançon Southampton Mönchengladbach Jüchen Forbach Bergheim Andover Oxford Saarbrücken Düsseldorf Köln Nantes Ratingen Leverkusen Bonn Oberhausen Couëron Solingen Essen Borken Wuppertal Gelsenkirchen Hattingen Mulhouse Koblenz Bendorf Saint-Nazaire Datteln Dortmund Kehl Müllheim Basel Lüdenscheid Saint-Brieuc Schwerte Lörrach Freiburg Limburg an der Lahn Vannes Wiesbaden Baden-Baden Netphen Mainz Worms Eggenstein-Leopoldshafen Karlsruhe Speyer Ludwigshafen am Rhein Rüsselsheim am Main Mannheim Lampertheim Newport Soest Eschborn Cardiff Bensheim Villingen-Schwenningen Darmstadt Warstein Heidelberg Wiesloch Lorient Frankfurt am Main Pforzheim Gießen Newton Abbot Zürich Marburg an der Lahn Roubaix Sainte-Geneviève-des-Bois Valenciennes Amiens Lille Le Havre Saint-Quentin Beveren Izegem Roeselare Dieppe Paris Krefeld Gent Maldegem Duisburg Menen Beauvais Evergem Rennes Kortrijk Mons Caen Rouen Étampes Liège Évreux Rambouillet Chartres Lisieux Alençon Dreux Andenne Tournai Angers Le Mans 14 Apr 15 16 17 18 19 20 21 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
Kortrijk Kortrijk, 14 April: 4.6 µg/m³, 0.5× usual Kortrijk, 15 April: 9.5 µg/m³, 1.1× usual Kortrijk, 16 April: 8.6 µg/m³, 1.0× usual Kortrijk, 17 April: 32.4 µg/m³, 3.7× usual Kortrijk, 18 April: 28.5 µg/m³, 3.2× usual Kortrijk, 19 April: 18.7 µg/m³, 2.1× usual Kortrijk, 20 April: 13.7 µg/m³, 1.6× usual Kortrijk, 21 April: 18.0 µg/m³, 2.0× usual Evergem Evergem, 14 April: 5.1 µg/m³, 0.6× usual Evergem, 15 April: 9.9 µg/m³, 1.1× usual Evergem, 16 April: 8.4 µg/m³, 0.9× usual Evergem, 17 April: 29.3 µg/m³, 3.2× usual Evergem, 18 April: 32.1 µg/m³, 3.5× usual Evergem, 19 April: 16.3 µg/m³, 1.8× usual Evergem, 20 April: 17.5 µg/m³, 1.9× usual Evergem, 21 April: 17.2 µg/m³, 1.9× usual Izegem Izegem, 14 April: 4.9 µg/m³, 0.5× usual Izegem, 15 April: 9.8 µg/m³, 1.0× usual Izegem, 16 April: 8.4 µg/m³, 0.9× usual Izegem, 17 April: 29.0 µg/m³, 3.0× usual Izegem, 18 April: 29.1 µg/m³, 3.0× usual Izegem, 19 April: 18.5 µg/m³, 1.9× usual Izegem, 20 April: 12.6 µg/m³, 1.3× usual Izegem, 21 April: 18.1 µg/m³, 1.8× usual Menen Menen, 14 April: 6.1 µg/m³, 0.7× usual Menen, 15 April: 9.2 µg/m³, 1.0× usual Menen, 16 April: 8.6 µg/m³, 1.0× usual Menen, 17 April: 28.8 µg/m³, 3.2× usual Menen, 18 April: 29.2 µg/m³, 3.2× usual Menen, 19 April: 19.3 µg/m³, 2.1× usual Menen, 20 April: 13.5 µg/m³, 1.5× usual Menen, 21 April: 18.2 µg/m³, 2.0× usual Roubaix Roubaix, 14 April: 5.6 µg/m³, 0.5× usual Roubaix, 15 April: 9.5 µg/m³, 0.8× usual Roubaix, 16 April: 6.9 µg/m³, 0.6× usual Roubaix, 17 April: 28.6 µg/m³, 2.4× usual Roubaix, 18 April: 27.0 µg/m³, 2.3× usual Roubaix, 19 April: 17.7 µg/m³, 1.5× usual Roubaix, 20 April: 11.4 µg/m³, 1.0× usual Roubaix, 21 April: 18.7 µg/m³, 1.6× usual Tournai Tournai, 14 April: 1.7 µg/m³, 0.3× usual Tournai, 15 April: 6.0 µg/m³, 1.1× usual Tournai, 16 April: 5.6 µg/m³, 1.1× usual Tournai, 17 April: 27.8 µg/m³, 5.2× usual Tournai, 18 April: 27.7 µg/m³, 5.2× usual Tournai, 19 April: 15.9 µg/m³, 3.0× usual Tournai, 20 April: 7.3 µg/m³, 1.4× usual Tournai, 21 April: 15.8 µg/m³, 3.0× usual Roeselare Roeselare, 14 April: 5.1 µg/m³, 0.5× usual Roeselare, 15 April: 9.9 µg/m³, 1.0× usual Roeselare, 16 April: 8.0 µg/m³, 0.8× usual Roeselare, 17 April: 27.6 µg/m³, 2.9× usual Roeselare, 18 April: 28.7 µg/m³, 3.0× usual Roeselare, 19 April: 19.7 µg/m³, 2.1× usual Roeselare, 20 April: 12.7 µg/m³, 1.3× usual Roeselare, 21 April: 19.2 µg/m³, 2.0× usual Krefeld Krefeld, 14 April: 10.3 µg/m³, 1.2× usual Krefeld, 15 April: 10.8 µg/m³, 1.2× usual Krefeld, 16 April: 16.6 µg/m³, 1.9× usual Krefeld, 17 April: 27.3 µg/m³, 3.1× usual Krefeld, 18 April: 22.3 µg/m³, 2.5× usual Krefeld, 19 April: 21.5 µg/m³, 2.4× usual Krefeld, 20 April: 20.2 µg/m³, 2.3× usual Krefeld, 21 April: 20.8 µg/m³, 2.3× usual Andenne Andenne, 14 April: 1.1 µg/m³, 0.2× usual Andenne, 15 April: 3.0 µg/m³, 0.6× usual Andenne, 16 April: 13.3 µg/m³, 2.5× usual Andenne, 17 April: 26.6 µg/m³, 5.0× usual Andenne, 18 April: 20.5 µg/m³, 3.9× usual Andenne, 19 April: 14.6 µg/m³, 2.8× usual Andenne, 20 April: 7.6 µg/m³, 1.4× usual Andenne, 21 April: 10.3 µg/m³, 1.9× usual Maldegem Maldegem, 14 April: 4.9 µg/m³, 0.6× usual Maldegem, 15 April: 9.7 µg/m³, 1.2× usual Maldegem, 16 April: 5.6 µg/m³, 0.7× usual Maldegem, 17 April: 26.1 µg/m³, 3.1× usual Maldegem, 18 April: 22.3 µg/m³, 2.7× usual Maldegem, 19 April: 15.5 µg/m³, 1.8× usual Maldegem, 20 April: 9.8 µg/m³, 1.2× usual Maldegem, 21 April: 19.3 µg/m³, 2.3× usual Duisburg Duisburg, 14 April: 8.6 µg/m³, 1.0× usual Duisburg, 15 April: 12.0 µg/m³, 1.5× usual Duisburg, 16 April: 19.4 µg/m³, 2.4× usual Duisburg, 17 April: 25.9 µg/m³, 3.2× usual Duisburg, 18 April: 15.5 µg/m³, 1.9× usual Duisburg, 19 April: 11.2 µg/m³, 1.4× usual Duisburg, 20 April: 11.5 µg/m³, 1.4× usual Duisburg, 21 April: 18.1 µg/m³, 2.2× usual Gent Gent, 14 April: 4.1 µg/m³, 0.5× usual Gent, 15 April: 9.2 µg/m³, 1.1× usual Gent, 16 April: 7.7 µg/m³, 0.9× usual Gent, 17 April: 25.7 µg/m³, 3.1× usual Gent, 18 April: 23.3 µg/m³, 2.8× usual Gent, 19 April: 14.2 µg/m³, 1.7× usual Gent, 20 April: 9.8 µg/m³, 1.2× usual Gent, 21 April: 14.0 µg/m³, 1.7× usual Lille Lille, 14 April: 4.1 µg/m³, 0.4× usual Lille, 15 April: 8.3 µg/m³, 0.9× usual Lille, 16 April: 6.4 µg/m³, 0.7× usual Lille, 17 April: 25.4 µg/m³, 2.7× usual Lille, 18 April: 25.9 µg/m³, 2.8× usual Lille, 19 April: 16.9 µg/m³, 1.8× usual Lille, 20 April: 9.9 µg/m³, 1.1× usual Lille, 21 April: 16.8 µg/m³, 1.8× usual Liège Liège, 14 April: 2.3 µg/m³, 0.4× usual Liège, 15 April: 2.9 µg/m³, 0.5× usual Liège, 16 April: 13.7 µg/m³, 2.3× usual Liège, 17 April: 25.2 µg/m³, 4.3× usual Liège, 18 April: 18.0 µg/m³, 3.1× usual Liège, 19 April: 13.8 µg/m³, 2.3× usual Liège, 20 April: 7.2 µg/m³, 1.2× usual Liège, 21 April: 8.2 µg/m³, 1.4× usual Mons Mons, 14 April: 2.0 µg/m³, 0.3× usual Mons, 15 April: 5.2 µg/m³, 0.8× usual Mons, 16 April: 13.2 µg/m³, 1.9× usual Mons, 17 April: 25.2 µg/m³, 3.7× usual Mons, 18 April: 24.4 µg/m³, 3.6× usual Mons, 19 April: 14.6 µg/m³, 2.1× usual Mons, 20 April: 8.4 µg/m³, 1.2× usual Mons, 21 April: 20.4 µg/m³, 3.0× usual Beveren Beveren, 14 April: 5.4 µg/m³, 0.7× usual Beveren, 15 April: 9.3 µg/m³, 1.1× usual Beveren, 16 April: 8.5 µg/m³, 1.0× usual Beveren, 17 April: 25.0 µg/m³, 3.0× usual Beveren, 18 April: 22.1 µg/m³, 2.7× usual Beveren, 19 April: 14.2 µg/m³, 1.7× usual Beveren, 20 April: 10.3 µg/m³, 1.3× usual Beveren, 21 April: 17.4 µg/m³, 2.1× usual Dreux Dreux, 14 April: 3.4 µg/m³, 0.5× usual Dreux, 15 April: 5.5 µg/m³, 0.8× usual Dreux, 16 April: 10.4 µg/m³, 1.5× usual Dreux, 17 April: 17.7 µg/m³, 2.6× usual Dreux, 18 April: 32.8 µg/m³, 4.8× usual Dreux, 19 April: 15.8 µg/m³, 2.3× usual Dreux, 20 April: 10.7 µg/m³, 1.6× usual Dreux, 21 April: 13.8 µg/m³, 2.0× usual Rouen Rouen, 14 April: 6.3 µg/m³, 0.8× usual Rouen, 15 April: 8.7 µg/m³, 1.1× usual Rouen, 16 April: 12.5 µg/m³, 1.6× usual Rouen, 17 April: 16.1 µg/m³, 2.0× usual Rouen, 18 April: 32.2 µg/m³, 4.1× usual Rouen, 19 April: 14.0 µg/m³, 1.8× usual Rouen, 20 April: 10.4 µg/m³, 1.3× usual Rouen, 21 April: 13.3 µg/m³, 1.7× usual Beauvais Beauvais, 14 April: 6.4 µg/m³, 0.7× usual Beauvais, 15 April: 6.4 µg/m³, 0.7× usual Beauvais, 16 April: 10.3 µg/m³, 1.2× usual Beauvais, 17 April: 20.5 µg/m³, 2.3× usual Beauvais, 18 April: 31.5 µg/m³, 3.5× usual Beauvais, 19 April: 12.5 µg/m³, 1.4× usual Beauvais, 20 April: 10.3 µg/m³, 1.2× usual Beauvais, 21 April: 12.7 µg/m³, 1.4× usual Chartres Chartres, 14 April: 3.6 µg/m³, 0.5× usual Chartres, 15 April: 4.2 µg/m³, 0.6× usual Chartres, 16 April: 10.4 µg/m³, 1.6× usual Chartres, 17 April: 17.0 µg/m³, 2.5× usual Chartres, 18 April: 31.0 µg/m³, 4.6× usual Chartres, 19 April: 10.5 µg/m³, 1.6× usual Chartres, 20 April: 9.5 µg/m³, 1.4× usual Chartres, 21 April: 12.9 µg/m³, 1.9× usual Lisieux Lisieux, 14 April: 3.4 µg/m³, 0.5× usual Lisieux, 15 April: 7.3 µg/m³, 1.1× usual Lisieux, 16 April: 11.9 µg/m³, 1.8× usual Lisieux, 17 April: 13.0 µg/m³, 1.9× usual Lisieux, 18 April: 30.9 µg/m³, 4.6× usual Lisieux, 19 April: 14.0 µg/m³, 2.1× usual Lisieux, 20 April: 9.5 µg/m³, 1.4× usual Lisieux, 21 April: 14.3 µg/m³, 2.1× usual Le Mans Le Mans, 14 April: 7.6 µg/m³, 1.4× usual Le Mans, 15 April: 4.4 µg/m³, 0.8× usual Le Mans, 16 April: 12.7 µg/m³, 2.3× usual Le Mans, 17 April: 12.7 µg/m³, 2.3× usual Le Mans, 18 April: 30.2 µg/m³, 5.4× usual Le Mans, 19 April: 14.1 µg/m³, 2.5× usual Le Mans, 20 April: 9.4 µg/m³, 1.7× usual Le Mans, 21 April: 15.3 µg/m³, 2.7× usual Rambouillet Rambouillet, 14 April: 3.7 µg/m³, 0.5× usual Rambouillet, 15 April: 4.6 µg/m³, 0.7× usual Rambouillet, 16 April: 10.6 µg/m³, 1.6× usual Rambouillet, 17 April: 17.0 µg/m³, 2.5× usual Rambouillet, 18 April: 29.8 µg/m³, 4.4× usual Rambouillet, 19 April: 10.4 µg/m³, 1.5× usual Rambouillet, 20 April: 10.4 µg/m³, 1.5× usual Rambouillet, 21 April: 12.2 µg/m³, 1.8× usual Angers Angers, 14 April: 5.2 µg/m³, 1.0× usual Angers, 15 April: 3.5 µg/m³, 0.6× usual Angers, 16 April: 7.8 µg/m³, 1.4× usual Angers, 17 April: 11.4 µg/m³, 2.1× usual Angers, 18 April: 29.2 µg/m³, 5.4× usual Angers, 19 April: 16.5 µg/m³, 3.1× usual Angers, 20 April: 9.4 µg/m³, 1.7× usual Angers, 21 April: 15.3 µg/m³, 2.8× usual Évreux Évreux, 14 April: 3.4 µg/m³, 0.5× usual Évreux, 15 April: 4.9 µg/m³, 0.8× usual Évreux, 16 April: 10.4 µg/m³, 1.6× usual Évreux, 17 April: 16.2 µg/m³, 2.5× usual Évreux, 18 April: 28.8 µg/m³, 4.4× usual Évreux, 19 April: 11.1 µg/m³, 1.7× usual Évreux, 20 April: 10.0 µg/m³, 1.5× usual Évreux, 21 April: 13.2 µg/m³, 2.0× usual Dieppe Dieppe, 14 April: 8.1 µg/m³, 0.9× usual Dieppe, 15 April: 11.2 µg/m³, 1.2× usual Dieppe, 16 April: 14.4 µg/m³, 1.6× usual Dieppe, 17 April: 21.2 µg/m³, 2.3× usual Dieppe, 18 April: 28.8 µg/m³, 3.1× usual Dieppe, 19 April: 16.7 µg/m³, 1.8× usual Dieppe, 20 April: 12.5 µg/m³, 1.4× usual Dieppe, 21 April: 22.8 µg/m³, 2.5× usual Alençon Alençon, 14 April: 3.3 µg/m³, 0.5× usual Alençon, 15 April: 4.2 µg/m³, 0.7× usual Alençon, 16 April: 9.1 µg/m³, 1.5× usual Alençon, 17 April: 10.2 µg/m³, 1.7× usual Alençon, 18 April: 28.5 µg/m³, 4.7× usual Alençon, 19 April: 13.4 µg/m³, 2.2× usual Alençon, 20 April: 9.2 µg/m³, 1.5× usual Alençon, 21 April: 14.4 µg/m³, 2.4× usual Paris Paris, 14 April: 6.2 µg/m³, 0.7× usual Paris, 15 April: 7.4 µg/m³, 0.8× usual Paris, 16 April: 9.6 µg/m³, 1.1× usual Paris, 17 April: 18.5 µg/m³, 2.1× usual Paris, 18 April: 27.6 µg/m³, 3.1× usual Paris, 19 April: 11.9 µg/m³, 1.3× usual Paris, 20 April: 11.1 µg/m³, 1.2× usual Paris, 21 April: 14.4 µg/m³, 1.6× usual Le Havre Le Havre, 14 April: 3.5 µg/m³, 0.4× usual Le Havre, 15 April: 5.4 µg/m³, 0.6× usual Le Havre, 16 April: 11.1 µg/m³, 1.2× usual Le Havre, 17 April: 15.9 µg/m³, 1.7× usual Le Havre, 18 April: 27.5 µg/m³, 3.0× usual Le Havre, 19 April: 15.1 µg/m³, 1.7× usual Le Havre, 20 April: 9.9 µg/m³, 1.1× usual Le Havre, 21 April: 19.4 µg/m³, 2.1× usual Caen Caen, 14 April: 3.3 µg/m³, 0.5× usual Caen, 15 April: 4.8 µg/m³, 0.7× usual Caen, 16 April: 9.0 µg/m³, 1.3× usual Caen, 17 April: 13.9 µg/m³, 2.1× usual Caen, 18 April: 27.1 µg/m³, 4.0× usual Caen, 19 April: 17.5 µg/m³, 2.6× usual Caen, 20 April: 10.0 µg/m³, 1.5× usual Caen, 21 April: 19.4 µg/m³, 2.9× usual Rennes Rennes, 14 April: 4.7 µg/m³, 0.6× usual Rennes, 15 April: 4.0 µg/m³, 0.5× usual Rennes, 16 April: 9.0 µg/m³, 1.2× usual Rennes, 17 April: 9.2 µg/m³, 1.3× usual Rennes, 18 April: 27.1 µg/m³, 3.7× usual Rennes, 19 April: 16.7 µg/m³, 2.3× usual Rennes, 20 April: 9.0 µg/m³, 1.2× usual Rennes, 21 April: 13.8 µg/m³, 1.9× usual Valenciennes Valenciennes, 14 April: 3.9 µg/m³, 0.4× usual Valenciennes, 15 April: 9.1 µg/m³, 0.9× usual Valenciennes, 16 April: 7.5 µg/m³, 0.7× usual Valenciennes, 17 April: 23.5 µg/m³, 2.2× usual Valenciennes, 18 April: 27.1 µg/m³, 2.6× usual Valenciennes, 19 April: 16.4 µg/m³, 1.6× usual Valenciennes, 20 April: 11.5 µg/m³, 1.1× usual Valenciennes, 21 April: 17.5 µg/m³, 1.7× usual Sainte-Geneviève-de… Sainte-Geneviève-des-Bois, 14 April: 11.9 µg/m³, 1.1× usual Sainte-Geneviève-des-Bois, 15 April: 10.4 µg/m³, 1.0× usual Sainte-Geneviève-des-Bois, 16 April: 11.4 µg/m³, 1.1× usual Sainte-Geneviève-des-Bois, 17 April: 20.2 µg/m³, 1.9× usual Sainte-Geneviève-des-Bois, 18 April: 26.5 µg/m³, 2.5× usual Sainte-Geneviève-des-Bois, 19 April: 10.2 µg/m³, 1.0× usual Sainte-Geneviève-des-Bois, 20 April: 11.9 µg/m³, 1.1× usual Sainte-Geneviève-des-Bois, 21 April: 18.1 µg/m³, 1.7× usual Saint-Quentin Saint-Quentin, 14 April: 4.5 µg/m³, 0.5× usual Saint-Quentin, 15 April: 8.7 µg/m³, 1.0× usual Saint-Quentin, 16 April: 8.7 µg/m³, 1.0× usual Saint-Quentin, 17 April: 20.4 µg/m³, 2.3× usual Saint-Quentin, 18 April: 25.9 µg/m³, 3.0× usual Saint-Quentin, 19 April: 10.4 µg/m³, 1.2× usual Saint-Quentin, 20 April: 10.8 µg/m³, 1.2× usual Saint-Quentin, 21 April: 13.5 µg/m³, 1.6× usual Étampes Étampes, 14 April: 3.2 µg/m³, 0.5× usual Étampes, 15 April: 3.7 µg/m³, 0.6× usual Étampes, 16 April: 9.8 µg/m³, 1.6× usual Étampes, 17 April: 17.4 µg/m³, 2.9× usual Étampes, 18 April: 25.6 µg/m³, 4.2× usual Étampes, 19 April: 10.6 µg/m³, 1.7× usual Étampes, 20 April: 10.0 µg/m³, 1.6× usual Étampes, 21 April: 12.1 µg/m³, 2.0× usual Amiens Amiens, 14 April: 4.8 µg/m³, 0.5× usual Amiens, 15 April: 6.0 µg/m³, 0.7× usual Amiens, 16 April: 9.1 µg/m³, 1.0× usual Amiens, 17 April: 19.6 µg/m³, 2.2× usual Amiens, 18 April: 25.6 µg/m³, 2.8× usual Amiens, 19 April: 13.5 µg/m³, 1.5× usual Amiens, 20 April: 9.3 µg/m³, 1.0× usual Amiens, 21 April: 15.2 µg/m³, 1.7× usual 14 Apr 15 16 17 18 19 20 21 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
Angers Pays de la Loire, France 1 18 April 5.4 5.4× Le Mans Pays de la Loire, France 1 18 April 5.6 5.4× Tournai Wallonia, Belgium 2 17 April 5.3 5.2× Andenne Wallonia, Belgium 1 17 April 5.3 5.0× Dreux Centre-Val de Loire, France 1 18 April 6.9 4.8× Alençon Normandy, France 1 18 April 6.1 4.7× Chartres Centre-Val de Loire, France 1 18 April 6.7 4.6× Lisieux Normandy, France 1 18 April 6.7 4.6× Évreux Normandy, France 1 18 April 6.5 4.4× Rambouillet Île-de-France, France 1 18 April 6.8 4.4× Liège Wallonia, Belgium 1 17 April 5.9 4.3× Étampes Île-de-France, France 1 18 April 6.1 4.2× Rouen Normandy, France 1 18 April 7.9 4.1× Caen Normandy, France 1 18 April 6.7 4.0× Rennes Brittany, France 1 18 April 7.3 3.7× Mons Wallonia, Belgium 1 17 April 6.8 3.7× Kortrijk Flanders, Belgium 2 17 April 8.8 3.7× Beauvais Hauts-de-France, France 1 18 April 8.9 3.5× Evergem Flanders, Belgium 2 18 April 9.1 3.5× Menen Flanders, Belgium 2 18 April 9.0 3.2× Duisburg North Rhine-Westphalia, Germany 1 17 April 8.2 3.2× Dieppe Normandy, France 1 18 April 9.2 3.1× Maldegem Flanders, Belgium 1 17 April 8.4 3.1× Paris Île-de-France, France 1 18 April 8.9 3.1× Gent Flanders, Belgium 1 17 April 8.3 3.1× Krefeld North Rhine-Westphalia, Germany 1 17 April 8.9 3.1× Beveren Flanders, Belgium 1 17 April 8.2 3.0× Le Havre Normandy, France 1 18 April 9.1 3.0× Roeselare Flanders, Belgium 2 18 April 9.6 3.0× Saint-Quentin Hauts-de-France, France 1 18 April 8.7 3.0× Izegem Flanders, Belgium 2 18 April 9.8 3.0× Amiens Hauts-de-France, France 1 18 April 9.0 2.8× Lille Hauts-de-France, France 2 18 April 9.4 2.8× Valenciennes Hauts-de-France, France 1 18 April 10.5 2.6× Sainte-Geneviève-des-Bois Île-de-France, France 1 18 April 10.7 2.5× Roubaix Hauts-de-France, France 2 17 April 11.9 2.4×
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 France and Belgium
Number 8 of 17 episodes in France and Belgium since our records began, by cities reached.
Central Europe, February and March 2023 274 Western Europe, March 2023 119 Southern Europe, December 2023 97 North-eastern Spain and France, February 2023 72 France, The Netherlands and United Kingdom, January 2023 66 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 Belgium and France, August 2023 15 United Kingdom, Belgium and France, June 2023 10 Flanders and Wallonia, Belgium, May 2023 10 Bars: cities reached; colour: the level of the episode's highest daily reading. All 17 .
Use this page SmogRank, France and Belgium, April 2023: 36 cities with PM2.5 at twice their usual or more, 17 to 18 April 2023, smogrank.com/episodes/2023-04-france-and-belgium (accessed 2 October 2026).
Copy citation 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.
