Blair will join Castleford in the UK on a deal that will see him remain a Tiger until at least the end of the 2022 season.
The 27-year-old played 38 games for the Storm over the past three-and-a-half years, and is looking forward to the opportunity to play for the Tigers.
“I am really excited and pumped to be joining the club. I am looking forward to getting over there, meeting everyone and ripping in,” Blair told castlefordtigers.com.
“I know Castleford have the best rugby league community and fans and I can’t wait to hear their roar!”