Sunny weather needs sunglasses – especially if you are driving.
I chose RayBan aviators with G10 grey tint. They have a low “side-bleed” and are optically excellent. I might have chosen polarization if i was in a high glare environment.
I swapped the RayBan case for an old Emporio Armani case with is tougher and much smaller – just big enough to hold the sunglasses.
Rainy weather needs a nice coat and hat, but an umbrella is highly desirable.
I chose a Fulton – Microslim – 2yrs ago. Only 25mm in diameter and 220mm long when folded and about 180g in weight. I have only used it 3 times but it worked well all three times.
Having reviewed the web – I think the time is nigh to review this choice. There are some very small Knirps and Fulton Umbrellas just entering production. For example: http://www.umbrellaworld.co.uk/mens-umbrellas/fulton-tiny-microslim-black-p-919.html