the water is not cold and air hits it
Yes and no. The waterfall itself does not freeze over. But with a prolonged freeze, an "ice bridge" may form in the river (below, I think).
A waterfall is made up of liquid water flowing downward over a cliff or rock surface. So, it is a liquid.
Yes, ice can form over waterfalls when the temperature is low enough for the water flowing over the falls to freeze. This can create beautiful ice formations and icicles on and around the waterfall.
Erosion and Freeze Thaw will steadily move the Waterfall backwards, although there are things in place to slow this process.
a waterfall.
It's easy. all you have to do is go to waterfall pond, silver trench, grand sea, faraway sea. water field and mt. freeze.
Khone
you have to get the HM waterfall to go over the waterfall
you use waterfall at the Pokemon waterfall or the battlefield.
a waterfall
there is a hm called waterfall
When using Surf outside of battle, and if there is a waterfall and you are at the bottom, you can travel up the waterfall by using Waterfall.