morning mist; morning haze
Refers to the thin mist or haze often seen in the early morning, especially in valleys or over water.
I like taking a walk in the morning mist.
川面に朝もやが立ちこめていた。
Morning mist hung over the river.
Common spelling using kana for もや; avoids the less common kanji 靄.
Kanji spelling; 靄 is a less common character, so 朝もや is often preferred.
Compound of 朝 (あさ, 'morning') and もや ('mist, haze'). The origin of もや is uncertain, but it is a native Japanese word for a light, thin mist.