Et-y-mol-o-gy I would forget if I did not write it down. Definition of Auspicious: 1. Attended by favorable circumstances; propitious. 2. Marked by prosperity or success. (Am.H., 2000). Now, here is an interesting usage point:
Purists have sometimes tried to limit the use of the adjective to meaning "of good omen," but the meaning has long since generalized to mean "favorable, successful": This has been an auspicious organizational meeting, one that gets the company off to a good start. (Columbia, 1993)
The purists are focusing on the word's Latin root "auspic-," which is also in the word auspice, an observer of birds. Auspicy is the practice of bird divination.
This is the kind of stuff that I love. I am with the purists on this one. We already have the word propitious, which means presenting favorable circumstances. No reason to take auspicious and make it into the same thing, kissing goodbye that special shade of meaning brought by the root word "auspic-" (i.e., the omen factor). The next time you find yourself using the word propitious, check your calendar. If it is January 1st, those favorable circumstances that you are describing are propitious if you only mean they have gotten the year off to a good start. BUT, if they signal the coming of a good year ahead, say auspicious, as in a birdly divined sign of good things to come. Flapping your wings is optional.