The western margin of the plateau descends through a broad transition zone called West Selengreyb. This region—roughly 60 miles wide—represents the slope between the high plateau and the lower Morelous plains.
West Selengreyb is where the katabatic winds are born. Cold, dense air pools on the plateau surface, then flows downhill under its own weight. The slope accelerates this flow, creating persistent winds of 40-60 mph that blast westward toward the coast. During cold snaps, these winds can exceed 100 mph—hurricane force—for days at a time.
The transition zone is worse than either the plateau or the plains. It combines the plateau's extreme cold with the plains' exposure, while the wind accelerates to its maximum velocity precisely in this band. No shelter exists; the slope is too consistent to create wind shadows. Crossing West Selengreyb is the most dangerous leg of any east-west journey through Venalthier.