thunderheaded

Swallows do this wherever they roost, but here they are dipping down to sleep through a thick dusk of tropical insects, a warm dew, a virtuoso frog chorus, tiny cigarette-glow fireflies lighting up, great thunderheaded clouds darkening on the horizon and pulses of lightning from far beyond it.

A Year on the Wing TIM DEE 2009

Then my eyes widened as this dark blue bald hulk with the billion eyes hooded up, rising up like a thunderheaded cobra slowly straight up before me, its hood flaring wide, its body arched, its purpose to strike right at me, to come at me, to overwhelm me, to bite me.

From Dust to Dust The Daily Growler 2006