GP's location that's unsatisfactory and wet (7)
I believe the answer is:
bahrain
'gp's location' is the definition.
'Bahrain' can be an answer for 'location' (Bahrain is an example). I'm not certain of the 'gp's' bit.
'unsatisfactory and wet' is the wordplay.
'unsatisfactory' becomes 'bah' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'and' is a charade indicator (letters next to each other).
'wet' becomes 'rain' (wet weather).
'bah'+'rain'='BAHRAIN'
'that's' is the link.
Can you help me to learn more?
(Other definitions for bahrain that I've seen before include "Gulf region?" , "kingdom in Middle East" , "Gulf state" , "Gulf sheikhdom, capital Manama" , "Island country in the Persian Gulf" .)