a feeling that trouble is coming

misgiving, bad omen

a statement about what is likely to happen, based on experience or scientific study

prediction, often of weather or business

(something, a happening, regarded as) a sign of something good or warning of evil fortune

sign of something to come

to be a sign or warning of (a future event etc)

foreshadow, indicate

an omen

indication, forewarning

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