If I am going early spring, late fall or will be in the mountains. I take a rain jacket with me. If I put a fleece jacket underneath, it is warm enough for being in cold weather as well. Also bought a cheap umbrella once, probably wouldn’t pack it because if I really need one I can buy it for a few euro.

For late spring, early fall and summer I carry a lightweight water repellent jacket and the smallest fold up umbrella I can find and I always have a shirt or T with long sleeves in the pack. I add layers for colder weather — like a micro-fleece (not bulky) work-out jacket as a jacket-liner. T shirt + long sleeved shirt + fleece +jacket is warm enough for most situations — you can always buy hat and gloves. For even colder weather, I highly recommend silk long underwear and/or a silk turtle neck.

If your fleece is bulky or you end up taking something like a down vest, look into one of those travel compression bags.

I usually just take a cheap lightweight rain jacket that weighs next to nothing. As even in the summer sudden thunderstorm’s are fairly common in central and Mediterranean Europe due to the build up of heat. Generally they last an hour then it’s great weather again. That’s from my experience in the summer anyway.