I'm another for whom winter is snow, not rain. (Although lately there's been precious little snow.) My pair love walking in any weather, but do not like to go out to go potty in the rain. Get a leash, and they are perfectly happy to go out. Lucy, on the hottest days of the year, will lay in the sun, on the driveway. Flora looks for shady grass. Of course, once they come back in, Lucy lays directly in front of the air conditioner. I guess she just likes some time in the dog sauna.
In winter, they get very efficient with potty breaks, but still enjoy long walks. Despite that, they refuse to wear jackets or booties (I've tried...). Flora is very funny in the snow because her legs are shorter, and the snow touches her tummy more often. To avoid plowing through snow, she jumps from one spot to another. She looks like a beagle-bunny!