forewarn about

forewarn (someone) about (something)

To inform someone of something in advance. Thanks for forewarning me about the boss's foul mood today—I made sure to steer clear of him.See also: forewarn

forewarn someone about something

 and forewarn someone of somethingto warn someone about someone or something. They forewarned us of your strange behavior. Didn't we forewarn you about Max's problem?See also: forewarn