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September 2012

Cloud of the Month for September 2012

September 2012

Italian Couture for Mountains

The cloud of the month for September was spotted by Sebastian Luciano Ferla over Monte Cofano in Sicily, Italy. Known as a ‘cap cloud’, it is the type that can sometimes be found floating jauntily over the top of a mountain peak. This cloud forms when a moist airstream has to rise to pass over the mountain. As it does so, the air expands and cools and, if the conditions are right, it can cool enough for some of its moisture to condense into tiny droplets, which collectivelly appear as a smooth dome of cloud.

There is an optical illusion at work in the appearance of a cap cloud like this. The cloud appears to hover motionless over the mountain peak even when the wind is brisk. In fact, the droplets of the cloud do zoom along with the wind. The reason the cloud seems stationary is because they all appear at the same point upwind of the mountain (where the air has cooled enough for them to form) and they all disappear at the same point in the lee of it (where the air dips back down and warms enough for them for evaporate away again). The cloud appears to be stationary as the droplets are flying through it. Only in the world of mountain cloud fashion, does a hat float magestically in place as a stiff wind whistles down the catwalk.

© Photograph Sebastian Luciano Ferla.

15 Comments
  • Jeannette Bisschoff

    September 5, 2012at3:04 pm

    Well captured, Sebastion, and thanks for sharing your awsome little cloud. Certainly deserves cloud of the month!

  • anna lightowler

    September 21, 2012at3:09 am

    great cloud!

  • Angela Bichard

    September 21, 2012at6:12 pm

    I just want to say how happy I am to receive your news letter I love looking at the videos especially the Halesworth UK one. Thank you

  • stephen seymour clancy

    September 21, 2012at8:38 pm

    Beautiful cloud against a perfect blue sky…pity we only a have horizon to horizon single grey cloud here in Orkney…we call it summertime.

  • John J. Smith

    September 21, 2012at11:33 pm

    Spectacular – nature produces some of the most monumental images – thank you for being in the right place at the right time congratulations

  • Geraldine Stroud avatar

    Geraldine Stroud

    September 22, 2012at7:55 pm

    Thank you for the news letter and Sebastian’s cloud photo is great – thanks! Just tried to capture a cloud looking like a massive hawk- you’ve guessed I couldn’t find the camera in time!! Will have the camera to hand in future!

  • Geraldine Stroud avatar

    Geraldine Stroud

    September 22, 2012at7:57 pm

    Great to receive the newsletter
    – thanks! Just tried to capture a cloud looking like a massive hawk- you’ve guessed I couldn’t find the camera in time!! Will have the camera to hand in future!

  • Norma Chalmers avatar

    Norma Chalmers

    September 23, 2012at3:21 am

    Ths lovely cap cloud reminds me that I once watched a cloud being born as I gazed at a brilliant blue sky over Mt Kosciusko, Australia. The couple of pixels first then swiftly the pixels magically expanded to be a flying white toddler. ow did tha happen? It flew and disolved before I could grab the camera. Gratefully, I captured the sight in memory forever.

  • Sharman Whitehead avatar

    Sharman Whitehead

    September 25, 2012at2:35 pm

    I loved the poem, it made me stop to think how beautiful the world is if we make time to look.

    Lovely cap cloud.

  • Nancy Riddick avatar

    N Riddick

    September 25, 2012at7:38 pm

    Why are some people so driven to prove what morons they are? Is this website about clouds or sexual fetishes?

  • Merle Smith avatar

    Merle L. Smith

    September 30, 2012at2:41 pm

    Great photo, it reminds me of a cloud I once saw above Table Mountain in South Africa.

  • Nicola Read avatar

    Nicola Read

    February 2, 2013at4:28 pm

    Love this pic. Shame there isnt a facebook “like” button to add it to my timeline, its so lovely!

  • radiometeolibera tv

    March 8, 2013at9:41 pm

    complimenti

  • alessandro barbolini

    March 8, 2013at9:41 pm

    siete un vero museo delle nuvole thank you

  • Shane yaw

    May 22, 2013at11:37 am

    i live there

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