WordNet sense 1 (contrary to your interests or welfare):

adverse, harmful, untoward

WordNet sense 2 (not encouraging or approving or pleasing):

unfavorable, unfavourable

WordNet sense 3 (presaging ill fortune):

ill, ominous

WordNet sense 4 (not propitious):

unpropitious

WordNet sense 5 (not auspicious; boding ill):

unfortunate