Climb Wind Page - Description
Climb winds are accessed in flight via the VERT REV page at a waypoint prior to the T/C waypoint, or via INIT page A during preflight.
During preflight the forecast enroute winds are uplinked (by LS 3R - WIND REQUEST) for the points that are loaded for departure and arrival airports. A temperature forecast is also uploaded for a default altitude near the Tropopause.
Winds can be manually entered too.