 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, which can occur up to four out of ten days in October.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.