WX and ACARS
as a AF B747 captain,i do confirm that we have a dedicated weather departement which occasionaly send some infos via ACARS in case of turbulence.
the last one i received (about turbulence)was when we were heading to FAI (AK, USA).
as long i can remember it was something like;
severe turbulence forecast from XXhrs valid till XX hrs.
position X° N X°W to Y° N Y°W.
from FL 250 to FL 410.
RIP