MONTREAL -- A smog warning is back in effect Tuesday afternoon with poor air quality being reported for most of southern Quebec, including the Greater Montreal area.

The Environment Canada warning was due to smoke from forest fires in northwestern Ontario.

The smog warning is in place for the following regions:

  • Eastern Townships
  • Gatineau
  • Lachute - Saint-Jérôme
  • Lanaudière
  • Metro Montréal - Laval
  • Richelieu Valley - Saint-Hyacinthe
  • Upper Gatineau - Lièvre - Papineau
  • Vaudreuil - Soulanges - Huntingdon

Gatineau and Vaudreuil-Soulanges-Huntingdon are also currently under a thunderstorm watch.

Environment Canada said there are high concentrations of fine particulates that are causing the poor air quality.

“Smog especially affects asthmatic children and people with respiratory ailments or heart disease,” the weather agency stated on its website. “It is therefore recommended that these individuals avoid intense physical activity outdoors until the smog warning is lifted.”

The conditions began Monday afternoon, were lifted Tuesday morning and were put back into place Tuesday afternoon.