promise vs forecast

promise and forecast both are nouns.

Word	Noun	Adjective	Verb	Adverb
promise	Yes	No	Yes	No
forecast	Yes	No	Yes	No

As verbs, forecast is a hyponym of promise; that is, forecast is a word with a more specific, narrower meaning than promise:

Other hyponyms of promise include read, outguess, second-guess, augur, bet, wager, calculate, prophesy, vaticinate.

promise (noun)	forecast (noun)
grounds for feeling hopeful about the future	a prediction about how something (as the weather) will develop
a verbal commitment by one person to another agreeing to do (or not to do) something in the future

promise (verb)	forecast (verb)
make a promise or commitment	judge to be probable
promise to undertake or give	predict in advance
make a prediction about; tell in advance	indicate, as with a sign or an omen
give grounds for expectations