Rare formations · feature
Asperitas clouds
An ocean above your head
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Own work
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Full credit
Own work
Displayed at reduced resolution. See the original file for full licensing information.
Full credit
Own work
Displayed at reduced resolution. See the original file for full licensing information.
Swipe or scroll sideways to explore the photographs. Photos may include other cloud types; names and credits come from their source records.
Spot it
A rough, irregular underside resembling a choppy sea.
How it forms
Wave-like motions deform a cloud layer; the detailed mechanism is still studied.
Read the sky
The dramatic texture itself does not establish severe weather at your location.
Where to look
Look beneath layered clouds with a strongly disturbed base.
Little sky facts
Reveal fact 1
Asperitas describes a rough cloud underside.
Reveal fact 2
Its waves are less regular than undulatus bands.
Reveal fact 3
Lighting can make the relief appear especially dramatic.
Reveal fact 4
It is a supplementary feature rather than an eleventh cloud genus.
Try this
Find a crest and a trough in the overhead sea.
Draw your own cloud ↗Read a little deeper
Met Office · formation and weather
Conditions described here are places to look, not a global frequency ranking. Use local weather forecasts and warnings for decisions. Never look directly at the Sun.