I love my old Belstaff Trialmaster. Pretty warm, and waterproof. Great on the bike, but excellent in the Mog.
Bought in he early 90's before they were popular and could charge silly money. Had a PPI payout last year and bought one for the Mrs.
Yes, I have a Barbour jacket that I use in warmer weather, especially if there's a bit of rain about. Mine's only about 15 years old so I've not needed to reproof it yet, but it's a good argument in favour of black vinyl seats