Howard struck from the penalty spot in the 58th minute, added his second 11 minutes from time and then completed his treble after 87 minutes as Leicester earned their first win in four games.
They had to do it the hard way as hey trailed to a 22nd minute strike from Robert Koren - the Slovenian's ninth goal of the season.
But Leicester took full advantage when Albion, who have now won just one of their last six home games, were reduced to ten men after Luke Moore was sent off for a foul on Richard Stearman in the 34th minute.
Gareth McAuley needed just four minutes to fire Leicester level before Howard destroyed Albion - doubling his tally of goals since his arrival from Leicester in just one game.
Albion, who survived an early scare when Leon Barnett cleared off the line from Barry Hayles, broke the deadlock after Zoltan Gera's right wing cross had forced McAuley to concede a corner.
Slovenia international Koren collected a short cross from Jonathan Greening and fired a 20-yard drive past Paul Henderson.
It looked to be the signal for Albion to take charge, but the game swung in a four-minute spell that saw Moore dismissed and McAuley equalise.
Referee Darren Deadman had no hesitation in sending off the on-loan Aston Villa striker for his crunching challenge on te Leicester right-back Stearman.
Albion paid the price for failing to come to terms with the loss of Moore. They were still reorganising themselves when goalkeeper Dean Kiely superbly tipped away a shot from Matty Fryatt.
But there was nothing that Kiely could do seconds later when Hayles played a short corner into the path of Joe Mattock, whose cross was headed home by McAuley from ten yards.
Kiely was equally powerless 13 minutes into the second half when Deadman had no hesitation in awarding a penalty after Barnett had bundled into Lee Hendrie and Howard comfortably converted from the spot.
Albion sent on strikers Sherjill MacDonald and Kevin Phillips in a bid to try and salvage something from the game.
But even the presence of 20-goal Phillips was not enough as he saw his 75th minute drive held on the line by Henderson.
Howard put the result beyond doubt when he latched on to a pass from Hendrie before beating Kiely with a low drive.
To add to Albion's problems, Barnett then limped off forcing Tony Mowbray's team to play with nine men and Howard took full advantage of the hole at the centre of defence to seal his treble with a low drive from the edge of the area.