Dripping Noise on Rear Passenger Panel

[scarface]

Ive noticed a dripping noise on rear passenger side door/boot. Was raining yesterday evening and noticed a tap like drip noise coming from rear passenger area. Ive noticed it before, but there is no water inside car and when i opened the door there were no visible signs of water inside door frame so not sure what or where its coming from.

Any ideas?

 

[Willie]

Pollen filter filling with water or could be Air con coolant dripping back into whence it came.

 

[scarface]

but isnt the pollen filter at front of car? dripping coming from rear

 

[Willie]

I didn't read your first post well enough.
Dunno what that could be, theres nothing in there.
Is you rear wash wiper working alright?
Getting a good spray out of the washers on the rear too?