Zeit, wieder nach draußen zu gehen

So since the air quality has gone up and the mist/fog thing is also completely gone, is it safe to assume that it was Smog ?

I’m no expert on these things but I think the air currents have changed after the temperature dropped by a few degrees, blowing away the polluted air here.

What is this app/site? To get at least sort of reliable info?

Must be from all those fresh, cool winds we got last night.