Synonyms and related words :
alarming, amazing, apocalyptic, astonishing, astounding, awe-inspiring, awesome, bad, baleful, baneful, black, bodeful, boding, dark, dire, doomful, dreary, earnest, evil, evil-starred, exceptional, extraordinary, fabulous, fantastic, fatal, fateful, foreboding, forerunning, forewarning, formidable, gloomy, grave, heavy, ill, ill-boding, ill-fated, ill-omened, ill-starred, imposing, inauspicious, indescribable, ineffable, legendary, lowering, marvelous, menacing, mind-boggling, miraculous, momentous, mythical, noteworthy, of evil portent, ominous, phenomenal, portending, precautional, precautionary, precursive, precursory, premonitory, prodigious, prodromal, prodromic, remarkable, serious, sinister, sober, solemn, somber, star-crossed, stupefying, stupendous, threatening, unexampled, unfavorable, unfortunate, unlucky, unparalleled, unprecedented, unpromising, unpropitious, unspeakable, untoward, weighty, wonderful, wondrous