The clouds collect the mosture and eventually when the water vapors get big enough they drop in the form of rain.
When warm air pushes into cold air the result is a warm front.
Warm air
An Warm air mass
Warm, humid
It is a warm front.
I pushes the warm air upwards.
It pushes the warm air above the cold air
When warm air pushes into cold air the result is a warm front.
Warm, humid
Warm air
Warm air
The cold air pushes under the warm air.
A warm air mass which would be cyclonic.
An Warm air mass
Warm, humid
Warm, humid
An Warm air mass