Batty woman visiting Alaska in warm jacket (6)
I believe the answer is:
anorak
'warm jacket' is the definition.
'anorak' can be an answer for 'jacket' (anorak is a kind of jacket). I am not sure about the 'warm' bit.
'batty woman visiting alaska' is the wordplay.
'batty woman' becomes 'Nora' (Nora Batty, Last of the Summer Wine character).
'visiting' is an insertion indicator.
'alaska' becomes 'ak' (I can't explain this - if you can you should believe this answer much more).
'nora' put within 'ak' is 'ANORAK'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for anorak that I've seen before include "Zipped jacket with hood attached" , "Arctic jacket: nerd" , "Garment (worn by boring obsessive?)" , "geek" , "Weather-resistant fabric" .)