Many people wrote off Wales' chances of challenging for the RBS 6 Nations title after they lost their tournament opener at home to Ireland.
Away victories against France, Italy and Scotland have reignited their challenge, while a seven-point win against Lancaster's men at the weekend will hand Howley and Wales the most unlikely of tournament titles.
Lancaster insists England's challenge at the Millennium Stadium is as big, if not bigger, than an autumn international against the mighty All Blacks.
And the England boss described Wales' patchy form in the build-up to the tournament, not as bad as the results indicate.
"People underestimate the tribal rivalry of the Six Nations," said Lancaster.
"It is very hard to win and the pressure can come on very quickly.
"But if you want to win a World Cup you have to be able to deal with it.
"This is a fantastic tournament and this weekend, which is an effective shoot-out, is great preparation for 2015.
"Sometimes winning and losing is portrayed as black and white but it's never like that in my opinion.
"The Welsh team did not go from reaching a World Cup semi-final and being Grand Slam champions to a team that was poor.
"The three games they lost to Australia they could have won all three and through the Six Nations they have grown in.
"Now they come into this game on the back of three away wins which is a great position to be in.
"Wales will be hugely motivated irrespective of what happened last week. Now they have a chance of winning the championship it raises the stakes."