Humid, dank (6)
I believe the answer is:
clammy
I believe this clue is a double definition.
'humid' is the first definition.
(synonyms)
'dank' is the second definition.
(synonyms)
(Other definitions for clammy that I've seen before include "Unpleasantly damp and sticky" , "Unpleasantly cool and humid" , "Stewing" , "Dank" , "Moist and adhesive" .)