Tommy spent the first nine years of his life in Nashville, the capital of the US state of Tennessee, before living in Dubai for a year as a result of his fatherís work commitments.
On his arrival in Northern Ireland, he was drafted straight into the Ulster Academy set-up where he has played the majority of his senior rugby. He earned his first full professional contract for the province in 2010 and has since made five appearances.
Tommy qualifies to play for Scotland thanks to his Glaswegian mother Sue.
Tommy has settled in well in Scotland and is keen to make an impression on his new club supporters. "I remember the supporters well from my time playing here with Ulster.
"Ulster maybe have a few more at the moment, but the Warriors support is very loyal, and noisy, and I don't think any team enjoyed coming to Firhill.
"I'm looking forward to getting the chance to run out in front of them in a Glasgow jersey, and give them something to shout about.
"People look at Ulster and their rise in the past two seasons, but they have built and built to where they are and I sense the same desire here.
"That was my reason for coming really. I could have stayed at Ulster, but that was an easy option.
"I wasn't starting regularly and while it's a good squad I felt I'd be resting on my laurels if I stayed, whereas coming to Glasgow would be a challenge, and if I succeeded it would have greater benefits."