On a flight from Hanoi to Kuala Lumpur.

Stratocumulus can have the form of Cumulus clouds that are joined-up to form a continuous layer. When the Cumulus are vigorous, their rising turrets make this cloud layer look a lot more dramatic from above than below – especially in the glancing rays of a low Sun.

Full classification:

Other examples of Stratocumulus:
Over The Marmolada, Italy.

Stratocumulus stratiformis

Over Berwick-upon-Tweed, Northumberland, UK.

Stratocumulus stratiformis