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Cloud spotting on Ocracoke Island, or…. ‘Excuse me. Your umbrella is in front of my cloud!’

Cumulus congestus seen from the pony pen beach, Ocracoke. Photo: C. Leinbach

Cumulus congestus seen from the pony pen beach, Ocracoke. Photo: C. Leinbach

The beautiful clouds of Ocracoke

By Danielle Creeksong

Ocracoke is well-loved for its spectacular, panoramic view of ocean and sky.  But while beach-goers pray for clear blue skies and star watchers wish for cloudless nights, if you ask around you will find an equal array of eager cloud-stalkers.

One silver-haired, self-professed “cloud nerd” named Mike parked on his beach chair sporting binoculars in one hand and a plastic spoon in the other. Held captive between his knees was a slightly squashed, fast-thawing pint of Ben & Jerry’s.

His focus?  Far offshore was a stunning, rapidly-blossoming line of rumbling thunderstorms pulsing internally with golden light.

“You’ve got the perfect environment for cloud-breeding out there,” he said. “That extra-warm Gulf Stream current water running like a river through cooler ocean waters.  Awesome!” A couple arrived and began setting up their umbrella slightly in front of Mike. Grumbling with annoyance, he gathered up his belongings and headed for another spot.

Cumulus humilis often appears here as a ‘cloud street’ like a long beaded necklace extending down the beach or on the sound. Photo by Ruth Fordon

But the Gulf Stream is not Ocracoke’s only cloud producer.  In summertime, high humidity and the near-steady water temps of the Pamlico Sound butt up against the rapidly changing temps of  mainland. This sharp difference in temperatures between land mass, ocean, and overriding air is all it takes to produce clouds and storms more typically associated with frontal boundaries. And, because they can build very suddenly even without a front attached, they catch the unsuspecting beach-goer by surprise.

Why be caught surprised? This common cloud sequence is easy for beginning cloud spotters:

Cumulus humilis – small, puffy but somewhat flat. Typically denote fair weather. Can portend storms later in the day if found in abundance in early morning. Can dissipate back into the atmosphere on a dry day.

Cumulus mediocris – as air becomes unstable, humilis will grow into mediocris, a cloud with more vertical puffiness. Rarely produces rain other than virga (rain which does not reach the earth).

Cumulus congestus – as warm air continues to rise, mediocris grows into congestus.  Referred to as a “cloud tower” when its  height exceeds its width. Can produce rain, but usually only light to moderate. Bottoms are often flat and black, and known here for producing “fair weather” (non-tornadic, usually F0 on the Fujita scale) waterspouts (see Ocracoke Observer, August 2016)

Cumulus mediocris, seen here in the Hatteras Inlet, can grow from cumulus humilis and are typical, puffy, fair-weather clouds. Photo: C. Leinbach

Cumulonimbus – when lightning strikes within congestus, cumulonimbus is born. But even without lightning, it is denoted by a horizontally-bulging cauliflower head, an obvious anvil-shaped top, or a top blowing out into wispy cirrus strands. May reach a height of 45,000 feet, its top freezing into ice crystals. Can also produce hail, torrential rains, strong wind gusts, and even tornadoes and tornadic waterspouts.

Still not convinced that cloud spotting should be your new hobby? Consider this quote from the founder of the British-based Cloud Appreciation Society:

“The digital world conspires to make us feel eternally, perpetually busy. Cloud spotting legitimizes ‘doing nothing,’ and doing nothing, being in the present. . . is good for your soul.”
            -– Gavin Pretor-Pinney
cloudappreciationsociety.org

Author’s note: The Cloud Appreciation Society currently has 43,407 members in 119 countries. Make that 43,408.

To read a related story on water spouts, click here.

A post-storm cumulus congestus, seen from the pony pen beach,Ocracoke, with an internal rainbow. Photo: C. Leinbach

A post-storm cumulus congestus, seen from the pony pen beach, with an internal rainbow. Photo: C. Leinbach

Cumulonimbus. Sometimes with lightning, sometimes without, these are the dramatic cloud castles seen all summer offshore. Photo: C. Leinbach

A cumulus congestus 'cloud tower' seen July 4 at the Lifeguard Beach, Ocracoke NC. Photo: C. Leinbach

A cumulus congestus ‘cloud tower’ seen July 4 at the Lifeguard Beach. Photo: C. Leinbach

Beautiful but bizarre, cumulonimbus arcus (shelf-type) made many appearances on Ocracoke and the Outer Banks in 2016. Containing powerful, visible gust fronts, they were ‘all bark and no bite’ except for an Aug. 8 storm with a funnel spotted offshore the Silver Lake ferry docks. this photo by Candace Owens of Grandy captures an arcus over the Currituck Sound. To view more about these clouds, click here.