This video, titled "[Hoshino Resort Tomamu] Unkai Terrace - Sea of clouds flowing into the sea of clouds (Unkai Terrace)" (【星野リゾート　トマム】雲海テラス　流れ込む雲海＜絶景＞ Unkai Terrace), was released by Hoshino Resort Tomamu (official).

This video introduces Unkai Terrace at the luxury resort "Hoshino Resort Tomamu" in Hokkaido.
Unkai Terrace is a superb spot at the Hoshino Resort Tomamu in Hokkaido where you can see the sea of clouds from above, and the overwhelming view of the grandeur of nature is nothing short of breathtaking.
The probability of seeing the sea of clouds itself is low, but it is a view that makes you want to see it at least once in person.

This video shows the actual view of the sea of clouds from Unkai Terrace, so if you're interested, be sure to check it out.