Fog advisory and rising humidity mark muggy start to September

Toronto stepped into September on Tuesday under thick fog, rising humidity and the risk of scattered showers and thunderstorms .

Environment Canada issued a yellow‑level fog advisory for the city and parts of the eastern GTA , warning of near‑zero visibility in pockets across Toronto, Pickering–Oshawa–Southern Durham, and Vaughan–Richmond Hill–Markham. The advisory has since ended as visibility improved later in the morning.

Mist and fog blanketed much of the region before sunrise, which created challenging conditions for commuters and prompting reminders from Canada’s weather agency to slow down and use headlights. With the fog now lifted, Toronto is expected to see a mix of cloud, sunny breaks and scattered showers, with the risk of thunderstorms developing through the day.