getting dark, growing darker
The sky is darkening.
Estava escurecendo e, para piorar, começou a chover.
It was getting dark and, to make matters worse, it started to rain.
Está escurecendo cada vez mais.
It's getting darker and darker.
Já estava escurecendo quando cheguei.
It was already getting dark when I arrived.
The clouds are darkening.
Não deveria estar escurecendo agora?
Shouldn't it be getting dark now?
— Os Mortos Não Morrem (2019)
It was getting dark.
It's getting dark outside.