Alas, the storm is come again!
William Shakespeare, "The Tempest", Act 2, Scene 2
Vortices, which present extra tropical and sub polar cyclone, differ from the Tropical cyclone under others by having other appearance and by containing different cloud structures. Therefore they are regarded like two different cloud structures.
The extra tropical cyclones look in Northern Hemisphere
as a comma.
The warm air, which flows in the high layer from the Tropics
toward the poles, is eastward diverted in Northern Hemisphere, due to
the Coriolis Effect. This causes there western prevailing winds. The near-surface
back-flowing cool polar air is diverted in western direction.
This cloud structure contains a number of different types
of the other cloud structures.
The cirrus clouds are forerunners of a cyclonic warm front
coming soon. They seal to large and deeper stratus and cirrostratus clouds.
The extra tropical cyclones are described detailed in literature and internet.
| Glob. occurr. diagram
of 'Extratropical Cyclone' System
ONLINE "Extratropical cyclone"
Cyclones: Vertical Structure