In Chapter 135 of the manga, One Punch Man finally reveals Blast's appearance in his superhero costume.

Is blast Saitama's dad?

This is because his appearance is going to be used as a plot point later. The big reveal is that when Saitama finally meets him, he will put two and two together and find out that Blast is his dad.

Will Saitama meet blast?

While he's only appeared in flashbacks and silhouettes thus far, top-ranked S-Class hero Blast finally appears in the present in the latest chapter of One-Punch Man. In the process, he meets Saitama, potentially saving the incredibly powerful hero from the same malevolent force that gave Psychos her powers.