When I was a kid/teenager, a rainy day in the summer meant a total overhaul of plans. As my normal form of transportation at the time was on foot or on my bike, both of my normal ways of getting together with friends were suddenly very unpleasant. Plans for the beach or the like were cancelled. I probably curled up with the telephone, to talk at length with my friends, and a good book.
Today was a rainy summer Tuesday. My daughter got up had something to eat and tidied a bit while waiting for her friend to be dropped off by car. They then proceeded to watch tv and play video games the whole day. Basically, it was business as usual for her. I am sad to say that going outside and being active is not in the usual cards for my kids. They do it sometimes and enjoy it, but only rarely.
For me, the rainy day involved getting wet going to and from the car when dropping off my other daughter at work, doing some housework, and curling up on the chouch with my kobo (the good book in the new century). For me the real change is the number of times I fell asleep on the couch while reading.