FOREWARN

[verb] [T] - to tell (someone) that something unpleasant is going to happenThere was no-one left in the village. They had obviously been forewarned about the raid. [T]The employees had been forewarned (that) the end-of-year financial results would be poor. [+ object + (that) clause](saying) 'Forewarned is forearmed' means that if you know about something before it happens, you can be prepared for it.