Air quality slowly improving in southern Quebec

Smoke from wildfires burning across northern Saskatchewan and Manitoba, produced some of the worst air quality on the planet in Montreal on both Friday and Saturday. Conditions began to improve on Sunday, and that trend should continue early in the week, with southwest winds and showers expected to"scrub" the air.

On Friday, southern Quebec and Ontario had some of the worst air quality among major cities on the planet. The hazy, smokey skies were created by high altitude smoke from the western Canadian wildfire, being driven closer to the surface on north winds. The result was a thick haze filtering out the sun and making it difficult on the eyes and respiratory systems. Air quality advisories were in effect for all our regions from Friday into Sunday morning before being lifted.

By no means is the air perfect Monday morning, with readings in Toronto and Montreal just under the unhealthy level on the air quality index at 94 and 93 respectively. That ranks the two cities 14th and 15th in the world Monday morning. Conditions should further improve late Monday as a warm front lifts north into the St. Lawrence Valley, accompanied by showers and southwest winds.

On Tuesday a cold front will generate showers and thunderstorms, with up to 10mm of rain possible. We need the moisture. To date, Montreal has only received 1.2mm of rain in June. The dry conditions have increased the risk of wildfires in the province, with SOPFEU reporting our region as extreme for fire risk. Outdoor burning should not be done under any circumstance in southwestern Quebec, until we receive some moisture. Conditions are expected to improve this week with the forecasted rainfall.

Temperatures this week will be seasonable, with daytime highs in the low to mid 20s and overnight lows in the middle teens. Unsettled weather, with showers and thunderstorms are likely from Monday afternoon into late Tuesday. By mid week, high pressure is expected to build into southern Quebec with plenty of sunshine to end the work week.