1. A clear umbrella like this one from Totes. These things are brilliant. I see commuters with these walking around not worrying about the wind and not running into people like I am with my flimsy little excuse for an umbrella and I think, "wow, that person is a genius, why didn't I think of that??" Not sure why I haven't bought one yet.
Hunter original rain wellies in a rainbow of colors. Wellies will never, ever be pretty on anyone I don't care what you say, but at least these have the reputation of being comfortable and as close to stylish as one can get wearing giant plastic boots. They're not cheap, but I'm pretty sure that these things will last a lifetime.
welly socks to go with the Hunter boots, which would make them wearable in the snow too.
Stella Grace rain coat. My husband makes fun of me because I already technically have a raincoat and why would I need another one? Well, I'm a grown-up on most days and I no longer want a bright blue rain coat that's why! I like this one because it's long enough and stylish enough to get away with at work, but also casual enough for everyday use.