prognosis vs forecasting

prognosis and forecasting both are nouns.

Word	Noun	Adjective	Verb	Adverb
prognosis	Yes	No	No	No
forecasting	Yes	No	No	No

As nouns, forecasting is a hypernym of prognosis; that is, forecasting is a word with a broader meaning than prognosis:

Other hypernyms of prognosis include foretelling, prediction, prognostication.

prognosis (noun)	forecasting (noun)
a prediction of the course of a disease	a statement made about the future
a prediction about how something (as the weather) will develop