Convergence Lines over Seas and Lakes
Competency Framework
WMO Satellite Skills
Application
Description
Small scale lines of convective cells as a result of confluence in a land/sea system.
Content
Convective bands are caused by low-level lines of convergence. They often develop in cold air outbreaks in which the coastal shape and sea-surface temperature pattern have a profound effect in establishing a low-level mesoscale circulation. Due to the large temperature difference between land and sea, offshore winds are generated. Convergence occurs when offshore winds, from opposite coasts meet each other. The cold air stream becomes unstable due to turbulent transport of sensible and latent heat from the warm sea surface. Convergence Lines form downwind of major bends in the coastline.