Inside a sealed dome, there would not be any significant wind, but in most shots outside, trees, people's hair, and clothing are blowing in the wind and the lake surface is choppy.
Although it is entirely possible to communicate with the outside world, the powers that be are never in contact with people from the outside, except for the episode where family is brought over to the dome.
While electromagnetic radiation such as radio waves are repeatedly shown to not pass through the dome (or at least to do so with difficulty and require specialised processing in order to be detected) nobody has any trouble seeing through the dome - visible light is nothing more than electromagnetic radiation. Attempts to fire lasers through the dome also apparently fail, but lasers are just intense light pulses and should also pass through unaffected.