Expected early moisture to be picked up? (3)
I believe the answer is:
due
'expected' is the definition.
(similar in meaning)
'early moisture to be picked up?' is the wordplay.
'early moisture' becomes 'dew' (moisture on the ground early in the morning).
'to be picked up?' indicates a 'sounds like' (homophone) clue (I've seen 'to be picked up' mean this).
'dew' is a homophone of 'DUE'.
(Other definitions for due that I've seen before include "...more than one there [ROME]" , "Appropriate - fee - now owing" , "Owed as a debt" , "Scheduled to arrive" , "Ripe for payment or arrival" .)