Megson managed the club from 2000 to 2004 during which time he led the West Midlanders up to the Premier League twice, in between a relegation.
Subsequently, Megson retains a special place in the hearts of the Baggies faithful for taking them to the top flight for the first time in 14 years, and current boss Mowbray expects that to be fully reflected in the crowd's reaction on Saturday.
"I would like to think he would get a very positive response. He achieved two promotions to the Premier League with this club. That is a wonderful achievement," said Mowray.
"I would hope the supporters show their appreciation of the good times Gary Megson had at the football club - but then, once the game gets rolling, I am sure they will be firmly behind West Brom."
'Fantastic' supportRegardless of the response that Megson gets on Saturday though, Mowbray has moved to express how he and his side are always confident of the support of the West Brom fans - through thick and thin.
"With our current predicament, many, many fans would have turned against their team by now - particularly with the nature of the goals we have conceded when we have been very competitive in games," admitted Mowbray.
"I have no idea why they are so positive. I would assume through history they have got a reputation of being positive and supportive of their side. That is fantastic and long many it continue.
"Can we turn it around? Within the ranks, the players think that and on the terraces. We need to get the results to keep motivating the fans to stick with the team.
"The team genuinely believe these next couple of games will give us the platform to push on and get the required wins to stay in the division."
PrideMuch of this unfaltering support of the team is likely to stem from the fans' respect for the attractive football that Mowbray's charges have strived to play this season.
Indeed, West Brom may be languishing six points from safety, but Mowbray believes that playing 'pure' football could yet save them from the drop.
"I sit on the touchline most weeks and say 'I am proud they are my team.' I enjoy watching them, the quality they show, the bravery they show going away and taking teams on and playing football," he added.
"I think it is the way forward. We aren't too far away from being a very competitive team, even in the top half of the Premier League - if we can survive this year and get the right couple of players in."