Wales could head into the game against Fiji having already qualified for the last eight of the competition, depending on the outcome of tomorrow's clash between South Africa and Samoa.
But the squad are focused their game on Sunday according to Howley and are looking to continue building the momentum.
"This tournament is all about momentum and confidence and this group of players certainly have that at the moment," said Howley.
"The mood is really good and there is a buzz around the squad.
"We have played well over the last few weeks and training has been really good as well.
"We are in really good shape physically and are extremely well conditioned and we have to go out on Sunday and nail the opportunities which are in front of us.
"We haven't spoken about the Fiji game from 2007 and it has no relevance on the game.
"We know what we have to do and are focused on that.
"Field position will be important and our collision dominance needs to be what it has been in recent weeks and it's important we focus on us and not look ahead of ourselves."
The squad to face the pacific islanders will be announced in the early hours on Friday morning (UK time) and Howley revealed that the injuries in the camp are progressing very well.
"Shane (Williams) came through a good session this morning but we are mindful that he is important to us and we might not select him for the weekend," he added.
"James (Hook) and Dan (Lydiate) are progressing nicely and hopefully by the early part of next week we should have a full compliment should we progress further."