In my home in Colorado, it's not unusual in a heatwave followed by freezing weather almost any time of the year. I have a lot of different coats and gear but it's a matter of how much I want to schlep. I also like to have a bit of style.
My go-to is a thigh-length, black rainshell with pockets and a zip-away hood that's bigger than I usually wear to fit over layers. I also have some lightweight merino wool (for warmer weather) and cashmere sweaters (for cooler weather) that I pack according to the forecast. In the after-holiday sales, I look for thin wool socks for the trip. Since I wear them all the time, my stock is pretty worn by the end of winter. Even in the summer, I bring one long-sleeved shirt for either warmth or sun protection.
This year, I added a down vest that covers my bottom. I'm considering adding some light gloves and a hat that will cover my ears but only if we'll be on the water or in the north. I've got a light thermal undershirt that might make the cut. The light cotton wrap I generally wear on the plan might morph into something more substantial. I can deal with cold but rain adds a whole other element. I'm undecided on umbrellas.
My biggest area of thought is shoes. Last year, I did the whole trip with one pair of Ecco low-cut shoes and my sister with low Merrill boots. It was great except in Venice. There is was raining torrential and we bought those ugly but functional plastic bubble boots that fit over our shoes. Looked dumb but it was nice to have dry feet. We've been thinking about what would be available in light, protective but supportive shoes. Our first vacation together, we brought a few pairs of shoes that were cute and we paid a heavy sore-foot price.
Last year, we traveled for three weeks with about 20 lbs each in rolling backpacks. That included some books and a picnic lunch kit. We'd planned to pare down this year.
and adding more shoes changes the equation. What are anybody's favorites?