上機嫌だ

be in a good mood

phrase Rare #29,203
be in a good mood Describes someone who is cheerful, pleased, or noticeably happy. 上機嫌 is commonly used with だ or だった.
JA: 試合に勝って、みんな上機嫌だった。
EN: Everyone was in a good mood after winning the game.

彼は今日は上機嫌だ

He’s in a good mood today.

トム上機嫌だ

Tom is in a good mood.

トム今日は上機嫌だなぁ

Tom is in a really good mood today.

ロビンソンさんの病気深刻なものだが、彼は上機嫌だ

Mr. Robinson's illness is serious, but he is in good spirits.