Mysterious and foreboding clouds against a dark purple backdrop

purple black background clouds sky ominous dark image thunderstorm moody mysterious atmosphere weather eerie foreboding nature dramatic contrast twilight evening dusk stormy evening sky purple clouds mysterious sky atmospheric brooding menacing gloomy dark sky purple background storm clouds chiaroscuro impending storm dusky sinister shadowy overcast purple sky moody atmosphere muted colors crepuscular grim unsettling intense impressive melancholic sinister beauty