We need rooftops over skateparks. 

Rainy days cause injuries. Water also ruins concrete over time. There would be less maintenance needed if we had rooftops.

The sun has a chance of giving sun cancer, while this is a small chance many of us spend hours and hours most of every year outside. Some shade from the heat would be nice. 

It gets so hot we can't skate our best until nighttime, leaving only a few hours of good skating time. 

It'll make us much better at skating, now that our country is competitive you should take a look at other countries skateparks. Theirs are getting better. 

I think about half or more japanese skateparks are indoor and very well designed, with a healthy mixture of indoor/outdoor/wood/concrete/transition/street. 

Meanwhile around here it's just. Concrete. Outdoor. Mostly street. 

At the very least, can we get some shade over our parks. 

To summarize, skatepark rooftops would make parks safer, more convenient, create better skaters, and preserve the parks itself.