Taking to Twitter the RTE star said: “Happy New Year to you and your loved ones tonight as we approach 2022.”
“I’m back at work tomorrow morning on RTE Radio 1 from 9 to 11am.”
Remembering his late mother he added: “My mother loved the radio so it’s a good place for me to start. Do join us if you can.”
Peggy Twomey, who was in her 90s died on December 7, following a single car collision near her home in Annagh, Miltown Malbay, Co Clare.
Following her tragic death, the commentator took time away from RTE to help deal with the loss.
On Christmas Eve he shared a message to thank fans for their support.
“The last few weeks has been the most difficult in my life as I lost my beautiful Mom so heartbreakingly,” he began.
“But my grief has been comforted by your wonderful love and support.”
“It’s a particularly hard time for a lot of people, especially this year more than most.”
“Life is precious. On this Christmas Eve night can I thank you from the bottom of my heart for your prayers, cards, phone calls and texts.”
“May I wish you and your family a very Happy Christmas and much love.”
Morrissey’s mother Peggy, whose maiden name was Twomey, was originally from Mallow, Co Cork, while his father Martin Morrissey came from Quilty in west Clare.
The sports presenter, who is an only child, lost his father on December 19, 2004.
In a recent interview with the Sunday Independent, the broadcaster described his father’s death as the saddest day of his life.
“He drove me to Shannon Airport from home. I said goodbye to him at departures,” he said.
His mother rang him when he arrived in New York to tell him the sad news and he said it was a “devastating blow” to the family.
Morrissey's parents left Ireland for New York as newlyweds in the early 1950s. There, his father set up a travel business, Morrissey Travel, in the Bronx.
Peggy, a former hairdresser, worked as a receptionist in a university.
When she became pregnant with Marty in 1958, she flew back to Ireland in order to have her baby in Cork. Marty was born at Mount Alvernia Hospital in Mallow.
Peggy returned to New York with her baby son one month later.
“She went back on one of those propeller planes for a 17-hour flight back to New York with me in her arms,” Marty said in recent years.
“It was some journey. She was brilliant, to be fair to her.”