There are men who have a certain panache, a certain je-ne-sais-quoi who can pull off the suit-without-a-tie look. They are not many. I am not among them. Most men are not among them. If you are already wearing a suit jacket, a necktie, unless it's strangulation tight, shouldn't increase your discomfort much in hot weather. Unfortunately, I don't think I have that panache(and it's too hot anyway!) Until the weather breaks, I think I'll go with dress slacks and a nice shirt. And with a venerable "Blue Blazer", kept at the office(and some ties of course). But if it's OK to "professional casual" in July, and August, who am I to argue!