Why is the weather in Tongan different from that in Xiamen Island?

Tongan is surrounded by mountains, Xiamen Island is surrounded by sea and seawater. Of course there is a difference.

Where there are mountains, it is easy to form cumulonimbus clouds, so it rains heavily when it rains;

Around the sea, the temperature difference between day and night is greater in places surrounded by mountains, because water can store and release heat.

In this way, although the distance between the two places is close, the weather forecast is often done separately.