stems from the adj. jubilant (showing great joy, satisfaction) an unforgettable, amazing, or undeniably incrediable chic and stellar time, place, article, person, thing. Or, an overwhelming feeling of joy, and fabulousness.
That skirt is like soooo JUBI!
The waves are looking mad JUBI today! Let's ride...
What a JUBI time!
I feel JUBI!
Like WOW! That was definitly JUBI.