Endure wet weather across East Midlands, initially (6)
I believe the answer is:
remain
'endure' is the definition.
(thesaurus)
'wet weather across east midlands initially' is the wordplay.
'wet weather' becomes 'rain' (I've seen this before).
'across' means one lot of letters goes inside another.
'initially' suggests taking the first letters.
The initial letters of 'east midlands' is 'em'.
'rain' going around 'em' is 'REMAIN'.
(Other definitions for remain that I've seen before include "Stay behind" , "Continue in position" , "Last" , "Stay on after others have gone" , "Airmen (anag.)" .)