Dark clouds were massing and it looked as if rain was only minutes away.

It was only 4:00, but dark clouds were massing again as though for attack.

The storm had died down, though more clouds were massing on the horizon.

Thunder rolled out of the west, building on itself where the clouds massed.

Those clouds that had kept the sun from troubling them were massing ever darker.

Dark clouds were massing in the east, another of those cursed storms coming.

Clouds massed outside the window; wind and thunder shook the room.

But she had no more time, not the way the Ebrans were moving, and the black clouds massing.

In time, the Liedfuhr's eyes turn toward the window and the clouds massing to the north.

Clouds were massing west, however, and there was a clear possibility of rain by nightfall.