The air in Сан Паулу feels heavy and a little smoky today, like the city is wrapped in a tired blanket. Breathing might seem a bit more of an effort if you step outside, especially in busier parts of town where the traffic is thick. It is not a day for long, carefree walks or throwing the windows wide open to let in the breeze, because the air itself is not doing us any favours.

If you are planning to exercise outside, it would be wise to take it easy or move your workout indoors instead. Children, older folks, and anyone who has a touch of breathing trouble or a heart condition might feel this air more than others, so it is sensible for them to stick to quieter, airier spots at home. The morning and evening rush seem to make things stuffier, so try to stay in when the streets are busiest.

That said, you can still open the windows for a quick airing when the sun is high and the streets are calmer, just don't leave them wide open all day. A short stroll to the corner shop is fine for most people, but if you start coughing or feel your chest tighten, head back inside and rest. The air is not dangerous for everyone, but it asks for a little patience and common sense.

The good news is that this kind of day usually passes, and tomorrow often brings a fresher feel. Keep a window cracked in a back room if you can, and maybe brew some tea while you wait for the air to clear. For today, just take it a bit slower, and Сан Паулу will feel like its old self again soon.