"The Morning Glory cloud - considered one of the world's most exotic meteorological phenomena - is best known from the Gulf of Carpentaria, northern Australia, where it is observed most often during spring, usually near dawn. The name "Morning Glory" reflects the often spectacular appearance of the long horizontal clouds at sunrise. . A Morning Glory cloud is a roll cloud that can be up to 1000 kilometers long, 1 to 2 kilometers high, and can move at speeds up to 40 kilometers per hour. "
Morning glory clouds have also been documented elsewhere, like the following in Sable Island, Canada, which, funnily enough, is itself shaped like a wave:
"Morning Glory, Sable Island, June 13, 2003. As the cloud approached, its position relative to the island was indicated by the long narrow shadow cast across the landscape, between the north and south beaches."
"View of the Morning Glory, looking towards the north, before and after it passed overhead. The front of the cloud was very smooth..."
"... the back was somewhat turbulent. The cloud was followed by a single line of scattered irregular cumulus."
"As the Morning Glory passed overhead, there was a drop in temperature, and a dramatic wind shift. This is a view to the north. looking along the underside of the cloud."
"The back of the cloud as it traveled westward. The laser ceilometer at the station measured the base of the cloud at 150 meters. The distance between the base of the cloud and its shadow on the ground indicated that the cloud itself must have had a depth of roughly 300 to 400 meters."Gliding over one of these rare atmospheric phenomena must be incredible.
Thanks to Leno for introducing me to this.
The Wave (Part One)
The Wave (Part Two)