Question about Air Conditioner

This is more of a technical question regarding the AC. I live in South Florida and the weather is really getting hot (well hotter than normal!). I've noticed that when I start the car the AC is blowing out cold air as it should but it appears not to be operating at full capacity (for lack of a better word). After a few miles the force of the air increases and it seems to get noticeably colder. Is this the way the system is designed? I don't seem to notice this in my gen III. Thanks folks!