Grand Canyon fills up with sea of clouds during rare weather phenomenon

A rare weather phenomenon known as a “total cloud inversion" had
visitors at the Grand Canyon looking out on a sea of thick clouds

A
rare weather phenomenon at the Grand Canyon in the US had visitors
looking out on a sea of thick clouds just below the rim on Thursday.

The total cloud inversion is expected to hang inside the canyon throughout Thursday.

The
National Weather Service says the weather event happens about once
every several years, though the landmark was treated to one last year.

The fog that has been shrouding parts of northern Arizona is courtesy of recent rains.

The Weather Service says the fog is able to stick around and built up in the Grand Canyon overnight when there is no wind.

With an inversion, the clouds are forced down by warm air and unable to rise.

The Grand Canyon is expected to gradually clear up in the coming days.

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