"It feels like it's raining in here"

Earlier this afternoon the sky began to get very dark and rain seemed to be looming. The establishment where I was eating lunch today was windowless (it was on a large ground floor of a highrise). It reminded me of a comment someone made a week ago when I was also in a windowless room (I hang out in some depressing places, I guess), and that person said, "Is it raining outside, because it feels like it's raining outside in here." I knew exaclty what she meant...the feeling when it seems darker, even if there are no windows around to bring the darkness to your visual attention.