On Tuesday 18 August 2026, the Interministerial Assessment Unit met for the second consecutive day to assess the latest information concerning the High Fens wildfire in Belgium and confirmed that the situation regarding its impact on Luxembourg had improved significantly.

On Monday 17 August 2026, the unit had reported that smoke from the wildfire had pushed PM10 fine particle concentrations above the alert threshold in Luxembourg.

According to the authorities, changing weather conditions have led to a favourable development regarding the impact of smoke on the Grand Duchy.

The wind has shifted to the west and south-west, with forecasts indicating that these conditions will remain in place until Friday 21 August 2026. The authorities said this should considerably limit the transport of smoke and fine particles towards Luxembourg and reduce their impact on air quality.

Fine particle concentrations currently remain low, although slightly above levels usually recorded in Luxembourg. The authorities expect this situation to continue over the next three days.

One monitoring station still recorded a daily PM10 concentration above 50 µg/m³ on Monday, mainly due to higher concentrations during the night. However, the situation has improved significantly since the afternoon, with measured concentrations remaining at satisfactory levels.

Based on the latest information, the authorities said no additional measures were considered necessary at this stage. People who notice smoke or are affected by its smell are urged to nevertheless continue following the previously issued precautions:

  • close doors and windows;

  • limit exposure to smoke as much as possible;

  • avoid prolonged physical activity outdoors when smoke or odours are significant;

  • where applicable, limit professional activities requiring significant physical effort when smoke or odours are significant;

  • temporarily switch off ventilation systems that bring in outside air where appropriate;

  • pay particular attention to vulnerable people, including babies and young children, elderly people, pregnant women and people with respiratory or cardiovascular conditions;

  • follow information and recommendations issued by the Luxembourg authorities through official channels.

Luxembourg authorities highlighted that they are continuing to monitor the situation and its possible impact on the country.