a feeling that trouble is coming

misgiving, bad omen

an omen

indication, forewarning

indicating correctly what will happen

telling of the future

the making known (of something secret or hidden); something surprising that is revealed

disclosure, telling

a mark, object, symbol etc used to represent something: 'mathematical sings' such as '+', '-', 'x', '?'; a word or words, design etc on a board or plate to give a warning, or to give direction; to write (one's name) on (a letter, application form etc)

indication, evidence

a strong feeling or reaction

indication, forewarning