Smoke from Canadian wildfires is blanketing Toronto and reducing air quality, according to reporting in both Canada and Taiwan. The National Weather Service says the smoke could persist into the end of the week, indicating that conditions may not improve immediately. Residents in Toronto are experiencing the effects of the haze, which can limit visibility and affect respiratory comfort. Multiple outlets describe the smoke as part of a broader air-quality problem driven by ongoing fires in Canada, with weather patterns carrying the pollution south and east. The situation is also described as a potential threat to U.S. cities, where similar smoke transport could lead to worsened air conditions depending on wind and atmospheric conditions. Overall, the coverage aligns on the main points: the source is wildfire smoke from Canada, Toronto is currently affected, and forecasters warn that the smoke is likely to linger and may impact parts of the United States later in the week.