Jump to content

Recommended Posts

Posted

Fallstreak Holes are a particular cloud formation also known as hole punch clouds.  I don't think I've ever seen one, but there's one on my BOM calendar and I'd never heard of the phenomenon.  Something to do with ice crystals and dominoes as quoted here from Wikipedia...

Quote

A fallstreak hole, also known as a hole punch cloud, punch hole cloud, skypunch, canal cloud or cloud hole, is a large circular or elliptical gap that can appear in cirrocumulus or altocumulus clouds. Such holes are formed when the water temperature in the clouds is below freezing but the water has not frozen yet due to the lack of ice nucleation (see supercooled water). When ice crystals do form it will set off a domino effect, due to the Bergeron process, causing the water droplets around the crystals to evaporate: this leaves a large, often circular, hole in the cloud.[1]

Spectacular looking clouds....

5686e4c782ee5_FallstreakHole1.jpg.bc66c45686e4c8e5a8d_FallstreakHole2.jpg.46f6945686e4ca9af01_FallstreakHole3.thumb.jpg.

Posted

They are an impressive cloud formation. We seem to get them in Central Queensland from time to time when the conditions are right, had a really good one a few months back that was massive.

Posted

They are amazing John. 

My favourite cloud formation is the undulatus asperatus clouds.  A rare-ish formation that is still waiting to be classified by the Cloud Appreciation Society. Seen them twice here, first time in January 2013 over Doncaster East and again nearer to Mount Dandenong in March 2014.

I love my weather watching :)

Undulatus_asperatus.jpg

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...