Altostratus undulatus cloud
Encyclopedia
The altostratus undulatus is a type of low altocumulus cloud
with signature undulations within it. These undulations may be visible (usually as "wavy bases"), but frequently they are indiscernible to the naked eye. These formations will generally appear in the early stages of destabilizing return flows, especially over the southern
plains
of the United States
, when the surface temperature is still relatively cool. The wavy strips of clouds are generally near an inversion surface.
Also referred to as billow clouds, wind row clouds, or wave clouds, variations of the undulatus can be elements that have merged or single elements that have stretched through the sky. They often run parallel, but can also appear to interweave across the sky, especially if dual wave systems are seen (also referred to as biundulatus). Gravity wave
s aligned normally to the direction of the wind can show wide, near-parallel cloud strips.
Altocumulus cloud
Altocumulus is a cloud belonging to a class characterized by globular masses or rolls in layers or patches, the individual elements being larger and darker than those of cirrocumulus and smaller than those of stratocumulus. Like other cumulus clouds, altocumulus signifies convection...
with signature undulations within it. These undulations may be visible (usually as "wavy bases"), but frequently they are indiscernible to the naked eye. These formations will generally appear in the early stages of destabilizing return flows, especially over the southern
Southern United States
The Southern United States—commonly referred to as the American South, Dixie, or simply the South—constitutes a large distinctive area in the southeastern and south-central United States...
plains
Great Plains
The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...
of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, when the surface temperature is still relatively cool. The wavy strips of clouds are generally near an inversion surface.
Also referred to as billow clouds, wind row clouds, or wave clouds, variations of the undulatus can be elements that have merged or single elements that have stretched through the sky. They often run parallel, but can also appear to interweave across the sky, especially if dual wave systems are seen (also referred to as biundulatus). Gravity wave
Gravity wave
In fluid dynamics, gravity waves are waves generated in a fluid medium or at the interface between two media which has the restoring force of gravity or buoyancy....
s aligned normally to the direction of the wind can show wide, near-parallel cloud strips.
External links
- American Meteorological Society's Glossary of Meteorology
- Stormeyes, a website for storm watchers (and storm chasersStorm chasingStorm chasing is broadly defined as the pursuit of any severe weather condition, regardless of motive, which can be curiosity, adventure, scientific exploration or for news professions/media coverage....
) - Weather Photography