在大雾天 英语是?1 在大雾天 / 外面是大雾2 今天天气闷热 翻译下，用哪个词好？闷热muggy 还有别的么。

in a foggy day
there is much fog outside

in a foggy day/It's foggy heavily outside。

in a dense fog 在大雾天
in a thick fog 在浓雾天
There is heavy fog outside. 外面是大雾

on a foggy day/ There's heavy fog outside.

in a foggy day
there is heavy fog outside
It is sultry today