I am so pleased we had the pushchair as it was loaded with a backpack with (for all 4 of us):
Towelling hoodies/GAP hoodies (worn most of the time)
Fleece (lightweight jackets)/Fleece lined hoodies (worn on top of the above at chilly times!)
Waterproof pac a macs (worn during the rain - obv)
And believe me, I think apart from one day, I think we all wore all of them at one point or another! I thought 3 coats per person was excessive but if I had the chance again I wouldn't have missed them.
I think the thing that got us the most was when it rained (or just before) it got quite cool, not freezing but enough to have a chill, then after the rain it got really hot - sun baking for a while???! It was very odd indeed. DD1 commented that all we needed was snow and we'd have had all seasons in one day

.
I also didn't take enough cardigans as even in the restaurants I felt a little chilly at times. I am a person that does feel the cold though. I am surprised it wasn't warmer but I think that might just be me!

We had better weather on our trip end Sept/early October!
ETA - Hopefully you won't need anything like that
