Morning Sun restores the user's current HP based on the weather and time of day. In day and at night, during no weather it restores ¼ total HP, during harsh sunlight it restores ½ total HP, and during other weather it restores ⅛ total HP. Except in link battles, the move restores twice as much HP in the morning.
Generation III onwards
Morning Sun restores the user's current HP based on the weather in the battle. During no weather or during strong winds it restores ½ total HP, during harsh sunlight it restores ⅔ total HP, and during other weather it restores ¼ total HP.
Morning Sun can be used as part of a Pokémon Contest combination, with the user gaining an extra appeal point if the move Sunny Day was used in the prior turn. It is also part of a Contest Spectacular combination and will give an extra three appeal points if the move Sunny Day was used in the prior turn.
If powered up by a Normalium Z into Z-Morning Sun, all of the user's lowered stats are reset.
Morning Sun heals all team members for a fixed amount of HP depending on the weather: 50 HP under clear weather, 80 HP under sunny weather, 40 HP under cloudy weather, 30 HP under sandstorm, 10 HP under rain and hail, and 1 HP under snow.
It restores the HP of you and your teammates in the same room. If it's sunny or in harsh sunlight, it restores your HP even more. During rain, heavy rain, hail, or a sandstorm, the amount regained goes down.
In the anime
Sparkles and rays of light surround the Pokémon's body, restoring HP.