Morning Glory Cloud

Bundy · Postby **Bundy** » Wed Sep 07, 2011 7:05 am

Hi guys,

: SANY0004.JPG (23.15 KiB) Viewed 3323 times

There is a thread on Avcom by a pilot in Australia who is planning a trip to go and witness this type of cloud. From what I have read, it is a roll cloud that can only form within specific conditions and is very rare. I was just wondering if we experience this type of cloud anywhere in SA?

It really is magnificent.

Regards,

Postby **John Boucher** » Wed Sep 07, 2011 4:34 pm

A roll cloud is a low, horizontal, tube-shaped, and relatively rare type of arcus cloud. They differ from shelf clouds by being completely detached from other cloud features. Roll clouds usually appear to be "rolling" about a horizontal axis. They are a solitary wave called a soliton, which is a wave that has a single crest and moves without changing speed or shape. One of the most famous frequent occurrences is the Morning Glory cloud in Queensland, Australia. One of the main causes of the Morning Glory cloud is the mesoscale circulation associated with sea breezes that develop over the Cape York peninsula and the Gulf of Carpentaria. However, similar features can be created by downdrafts from thunderstorms and are not exclusively associated with coastal regions. Coastal roll clouds have been seen over California, the English Channel, Shetland Islands, Lithuania, Eastern Russia, other maritime regions of Australia, off the Mexican coast in the Sea of Cortez, Uruguay, in the Canadian provinces of Nova Scotia and Ontario, and Campos dos Goytacazes and Coronel Vivida bay in Brazil.

http://www.youtube.com/watch?v=hKI2Atj08Xk

AndyG · Postby **AndyG** » Wed Sep 07, 2011 5:12 pm

Thanks for the info Mr Researcher Stirrer Boucher

Boet · Postby **Boet** » Wed Sep 07, 2011 6:51 pm

Also forms here near my hometown, in winter. Very nice for some ridge soaring, but stay away from 1 the cloud and 2 the downwind side of the cloud.

Postby **John Boucher** » Thu Sep 08, 2011 9:14 am

It is my sincere pleasure Andy....

You know, the Yanks always boast that everything is bigger and better in the USA - well, they may be right in certain areas.... their STORMS, ARCUS clouds, HAIL, ROCKETS, ARSEHOLES (debateable

) do seem serious stuff!

Looking at some of the youtube footage... eish, some Super CB's I really don't want to be close to. Not to be outdone, the Aussies also wanna start boasting with their SuperCells like the one in Perth!

But here's the conspiracy thing........ there are those that say all these amazing occurrences are the result of HAARP

http://www.haarp.alaska.edu/

Be afraid.... be very afraid!

Bundy · Postby **Bundy** » Thu Sep 08, 2011 2:06 pm

On the subject of CB's, here are a few good reasons to stay on the ground!

Nature can be terifyingly beautiful..... as long as you are'nt in the air!

Postby **John Boucher** » Thu Sep 08, 2011 2:19 pm

The top photo is of Mammoth clouds... got photos of them just before serious Charlie B activity in Kimberley when I still lived there.... !

AndyG · Postby **AndyG** » Fri Sep 09, 2011 7:39 am

Mammatus clouds John.

Postby **John Boucher** » Fri Sep 09, 2011 8:57 am

Goeie more klas.... sit maar!

Actually Andy you are correct. Using the term Mammoth is slang for being large and we blame the Yanks for this. Correctly termed "mammatocumulus" (meaning "mammary cloud" or "breast cloud") The name mammatus is derived from the Latin word "mamma" which means either "udder" or "breast". It has the mammary connotation and hence refers to that of a woman's breast....

Ons gee vandag 'n goue sterretjie vir Andy....

AndyG · Postby **AndyG** » Fri Sep 09, 2011 9:41 am

JB I know that you are obsessed with breasts but this takes it to a new level!!!

Jean Crous · Postby **Jean Crous** » Sun Sep 11, 2011 1:13 pm

John obviously knows what is of interest

John Young · Postby **John Young** » Mon Sep 12, 2011 10:05 am

John Boucher wrote:You know, the Yanks always boast that everything is bigger and better in the USA - well, they may be right in certain areas.... their STORMS, ARCUS clouds, HAIL, ROCKETS, ARSEHOLES (debateable )

Hey JB,

I still got connections in SA to "breaka your foot and cut off da B@lls" - affirm?

Regards Oh Stirrer
John

John Young · Postby **John Young** » Mon Sep 12, 2011 10:08 am

AndyG wrote:Mammatus clouds John.

Hi Andy,

Spot on - the WX Men call them "mamatosies" in slang - they appear under CB's.

Regards
John

Postby **John Boucher** » Mon Sep 12, 2011 10:21 am

You're not a "Yank" yet so.... you may be exempt from the arsehole bit for some time....

Petrodactyl · Postby **Petrodactyl** » Tue Sep 13, 2011 11:35 am

Look how quickly these threads degenerate and stray from the topic, but no surprise. From Mammoths to Mammaries .. and yet no chirp about Morning Glories.

Great cloud pics, though, and now that I have my copy of 'Understanding the Sky' I have a better understanding of what I am looking at.