Favorable, benign, auspicious, propitious mean being of good omen or presaging a happy or successful outcome.
Favorable implies that the persons or circumstances involved tend to assist in attaining one’s ends—persons by being kindly disposed or actually helpful and circumstances by being distinctly advantageous or encouraging.
Benign (see also KIND ) is applicable chiefly to someone or to something that has power to make or mar one’s fortunes by his or its aspect and is thought of as looking down with favor on one or of presenting a favorable countenance to one.
Auspicious, like the related augur (see under FORETELL ), suggests the presence of signs or omens and is applicable to something that is marked by favorable signs or is in itself regarded as a good omen.
Propitious suggests an allusion to favoring gods or powers more strongly than favorable but not quite so explicitly as auspicious ; it may therefore be preferred to favorable when such a connotation is desired.