We might have gleaned more information if you knew what to look for in the shapes the crows were makin'. You know that raven crows and magpies are all part of de same genus and are often considered interchangeable in the lore? Crows are more associated with the city than dere cousins though so dat could be significant or it could just be that's what Raven had available. Divination isn't an exact science you know. You described a procession of seven geometric shapes, dis is most assuredly significant. There is an old divination rhyme associated with Raven. "One for sorrow, two for joy, three for a girl, four for a boy, five for silver six for gold, seven for a secret never to be told". If you could remember what shapes they used dat might have given us more information. De rest of it is about a danger from the sea, or possibly one of the islands in that direction.
Based on what you saw and and my own experiences I would say dat an ancient menace from de sea is stirring. Ancient horrors from de fourt Age have stirred mens dreams for millennia. I would be especially wary of Dagon, his cultists are blood mages and the occasional toxic shaman and he is de most closely associated with de sea.. You may be called upon to do battle wit dese abominations.
