Learning spanish in BA


Hola Todos.
I will be completing 2 years of Spanish language classes in the US soon and I plan to continue my studies in Buenos Aires in July. I understand that Argentines speak a dialect called Platense. Will I be taught the Argentine dialect or formal spanish? The last time I was in BA in 2003. I had trouble being understood and understanding the Porteneos. What will the weather be like in July?