Prepare clothing around specific areas along the route, altitude, and day-night temperature differences. Lightweight layers and weatherproof outer layers are often more practical than heavy items with multiple straps.
Check the forecast again a week before departure
Seasonal averages fit the general direction, but only in the last week do you need to adjust your shoes, rain gear, and daily bag accordingly.
Packing for real activities
Cities are the focus, mountain routes, and high-speed rail are packed with itineraries, so the requirements for shoes and layers are different. Don't pack for your imagined trips.