Parousia does indeed mean presence. But in the context that Jesus used it it has the functional equivalent of coming. In Matthew 24 Jesus uses coming and presence interchangeably because he has to first come in order to be present. So to speak of his presence means to also implicitly refer to his coming since he only becomes present as a result of his coming.
Watchtower foolishly wants people to believe that Jesus becomes present before he comes, which is a foolishly illogical concept that can only spring from the mind of false prophet desperate to cover up his false prophecy.
A careful reading of Matthew 24 would reveal that when Jesus said no one knows the day or hour, he was actually speaking of his presence - which is the inevitable result of his final coming (you cannot separate the two like the JWs are attempting to) . Immediately after saying no one knows the day or the hour he starts off with the word "For", which is another way of saying "because" then he speaks of his "presence" being just as what happened in the days of Noah. Thus he was actually saying that the day of his presence would be unknown! He compared this to the people of Noah's day not knowing the day the flood would come and so it caught them by surprize doing everyday activities. Look at the Greek! That's exactly what he was saying! He was saying no one knew but Watchtower mistranslates it as "they took no note".
Then we have 2 Peter 3 where Peter consistently uses "presence" to refer to christ's actual final coming to destroy the wicked world. It is clear from the NT that "presence" of christ does not refer to a century long invisible presence as the JWs claim.