No rain was falling there in the heart of the city, but the clouds hung low, and threatened.

The clouds were still threatening to the west but as yet were a long way off.

He talked about the energy of the weekends on a warm evening compared with those nights when clouds threaten.

The weather remained pleasant, although the gray clouds far on the horizon threatened more rain.

The wind from the north blew fair, though the gray clouds threatened a winter gale.

Abruptly there were clouds in the sky, threatening billows of gray and black.

Anna glanced around, but while the clouds threatened, for the moment nothing fell from them but light rain.

This particular day had not begun so auspiciously, with dark gray clouds threatening overhead most of the morning.

Diana pointed out that great clouds had rolled up again and threatened the same downpour of rain as the night before.

Dark clouds threatened to shorten or cancel the event and the conditions were even more challenging for the athletes.