Is the gloom of the sky lit by the dark cloud passing by?
It seems as though the sky is gloomy, and when the dark cloud passes, light breaks through.
That's how I interpreted it, and can relate it to when, say, a writer is sad or depressed, it can bring about great works of art and word!
Although negative emotion can manifest itself in bad ways, it can be manifested and placed into different mediums and cause greatness!
Here's a stab at a haiku:
Five syllables, hard
Seven syllables, easy
Five more, a bit hard