It isn't usually very thick, and often occurs in the mountains or near the sea. Fog, mist or smog?
Mist
Unpleasantly hot. It's...
It's boiling / It's scorching
Unpleasantly cold. It's...
It's chilly
-12°C. It's...
It's below zero
Quite cold. It's...
It's cool
It is thicker, and can be found in towns and in the country. Fog, mist or smog?
Fog
Raining a lot. It's...
It's pouring
Raining intermittently. There...
There are showers
Very cold. It's...
It's freezing
A pleasantly high temperature. It's...
It's warm
Cold and slightly wet. It's...
It's damp
Raining lightly. It's...
It's drizzling
Warm and wet, but not raining. It's...
It's humid.
It is caused by pollution and usually occurs in big cities. Fog, mist or smog?
Smog
Pleasant and not cold. It's...
It's mild
Light wind. There...
There's a breeze