Mothers were there with their sons and daughters to buy school uniforms for the new term while, a short distance away, excited youngsters on 14 floats put the finishing touches to fancy dress costumes and face paintings.
Shoppers had been evacuated from one end of the high street because of a bomb scare, but no one took it too seriously. It happened all the time.
And then the bomb went off. In a split second, the force of the blast along with shrapnel and shards of glass had taken their toll on flesh and bone. Dozens lay dead or dying and, as masonry dust and smoke cleared, scenes of unimaginable horror greeted the survivors.
It was 3.10pm. The earlier bomb warning had been made in a telephone call to the BBC. The caller said the device was at the courthouse in Main Street. Police reacted quickly, clearing the area and shepherding people to the other end of the street, inadvertently leading them, like lambs to the slaughter, towards the real site of the 500lb car bomb near the junction of Market Street and Dublin Road.
When it went off, hundreds of shoppers, predominantly women and children, were near by. Ten minutes later, the carnival procession would have been in full flow.
The blast brought down walls and roofs on top of people and sent bricks and glass hurtling into them. When the noise subsided, witnesses spoke of seeing people with horrific injuries lying motionless while others screamed hysterically or walked aimlessly in deep shock.
"The first thing I saw was a wee boy lying with his mouth open and his eyes open and blood all over him. He was dead," said Louis Godfrey, 18. "He was about six years old.
"There was one girl about 21 who just sat there hugging this wee fella who was dead. He was about eight years old. She didn't want to let him go. She said she wanted to stay with him until his parents came. She kept saying over and over, `What has he ever done on anybody? He's so young. He doesn't even know the meaning of life'. Eventually a policeman persuaded her to let go."
While bloodsoaked survivors and policemen began tearing at the rubble to pull out the injured, panic began to spread as people from other parts of the town rushed to the scene to search for relatives.
Dorothy Boyle, 59, wept openly as she described the scene. "I saw bodies lying everywhere," she said. "I saw them being put in bags and being zipped up."
She said she saw a young pregnant woman whose legs had been blown off, while another woman in a wheelchair had been screaming for help. "There was one boy had half his leg blown off and it was lying there with the wee shoe still on it. He didn't cry or anything. He was just in shock."
Ian Frew was working in the Salad Bowl shop close to the bomb when it went off. Standing in a bloodstained T-shirt, he said: "Everybody just dropped. People lay dead all around. There was a baby lying in the window of Kells shop. It was just lying there dead, its pushchair standing beside it."
John Atkins, who had been shopping with his wife Ellen said: "For the first time I realised there was a smell to blood. I thought this was what an abattoir must smell like. Then I was disgusted with myself for even thinking that. These were people, men, women and children ..."
It was only by good fortune that there were not many more children at the scene of the explosion, said community worker Gerry McCusker. "The original plan was for 14 floats of children to set off from where the bomb had been planted but we decided earlier on we would move it. Thank God."
At 3.11pm, staff at the Tyrone County Hospital were put on an emergency footing and an appeal went out for off-duty doctors and nurses to report for duty.
Taxi drivers and motorists helped a stream of ambulances take the injured for treatment. The town's phone lines went dead for a time, and traffic jams built up as anxious people made their way to the hospital in search of relatives. Paddy McGowan, a local councillor, flagged down two buses to ferry the injured to hospital. "It was like a battlefield," he said. "There were scores of injured, seriously injured. People were running looking for their children. I've never seen devastation like it. It was a busy market day. I can't understand the mentality of whoever did this."
The steps of Tyrone County Hospital were covered in blood. Inside, doctors and nurses worked desperately to save the victims amid chaotic scenes.
One woman was rushing around touching at the sleeves of officials and pleading: "Have you seen my boy? He's just a wee boy. He went out to the shops he hasn't been back." A nurse asked for the child's name and the woman replied: "He's my boy, he's my only son."
Father John Gilmore did what he could to comfort the injured and their relatives.. "There were people on the floors, mattresses and chairs. Some of the early ones were very badly injured. Some I anointed on mattresses on the floor. It is something I have never experienced before.
"Every one of those people was a tragedy in their own right. When you think of how many, you have to think of the scale of the tragedy."
Dr Clive Russell and his team worked to the point of exhaustion as a steady stream of victims arrived needing emergency treatment. The 148 people they treated ranged from babies and young children to pensioners. Two young children had leg amputations. One 10-year-old victim lost a foot.
When asked whether that victim was a boy or a girl, Dr Russell's fatigue became apparent. He paused for a while before replying: "I can't remember."
Most of the injuries were caused by shrapnel and flying glass. Some needing specialist treatment were driven or airlifted to other hospitals. Dominic Pinto, senior consultant surgeon at Tyrone County Hospital, said that, in "one or two" cases, staff had seen their own relatives being brought in among the injured. "Unfortunately," he said, "one case was quite severe."
Twenty-two of the most serious cases were treated at the Royal Victoria Hospital in Belfast. They included three Spaniards who had been visiting Omagh on a student exchange programme. Two Spaniards were among the dead.
Gerry Carson, hospital spokesman, said: "We put our emergency plan into operation. There were helicopters landing in the car park until late into the evening."
Back in Omagh, the local leisure centre was used as a casualty field hospital. Dozens of relatives waited outside as lists of those being treated inside were pinned to a noticeboard. When names were recognised, there was relief mixed with apprehension over how serious the injuries would turn out to be.
Priests, social workers, police, medical staff and local politicians offered assistance to those whose loved ones had died. Families who had been given bad news were often driven off by taxis whose drivers made their vehicles available to anyone needing transport to homes or hospitals.
Lindsay Hall found out that his wife, Gwen, and son Alastair, 12, had been caught in the blast. They were alive, but Alastair had lost one of his legs. Bewildered, he asked: "How could they do this to innocent, ordinary people on a Saturday afternoon? Alastair loved playing rugby but he will never be able to again now. He was out with his mum buying some trousers for going back to school when the warning came. They came out of the shop and tried to get back to the car. If they'd stayed in the shop they would both have been killed. He's only 12. I'm 57, why couldn't it have happened to me?"
For others, moments of panic turned into relief as relatives were found safe and well. Darryl Simpson was separated from members of his family while panic mounted over their fate. "I ended up checking bodies trying to see if they were my ones," he said.
"It seems selfish talking about it now but it was all I could think about at the time. It was an anxious two-hour wait before we could establish where they were. All of our family, all nine of us, stayed together in the one bedroom last night."
The town woke up yesterday to grey skies and drizzle and a sense of disbelief. People gathered at the scene and shook their heads, appalled at the devastation, morbidly fascinated by the crater in the road and the barely recognisable remains of the maroon Vauxhall Astra that bore the bomb.
The pavement was covered in dried blood. Among the wreckage were nappies, a mangled pram and a pair of children's shoes.
Congregations for morning services were swelled by a need to share grief. More than 800 people squeezed into St Joseph's Hall next to the Catholic Church of the Sacred Heart to be told that one of the victims was from their ranks. Geraldine Breslin, a young married woman, died from her wounds early yesterday.
Some sat weeping, others stared vacantly as Father Michael Keaveny said the atrocity had nothing to do with religion. "From the point of view of the people who suffered there was no distinction, Catholic and Protestant, young and old, there was no question of wanting to get one side rather than another," he said.
"The whole thing sounds so terrible, so stupid, so foolish, so senseless."
One parishioner, Patrick Darcy, said: "I feel diminished as an Irishman that other Irishmen could come to this town and scatter the blood of Irish men, women and children over these streets."
All day, politicians came and went, genuinely distressed by what they saw. Tony Blair, the Prime Minister, John Prescott, his deputy, Mo Mowlam, the Secretary of State for Northern Ireland, Bertie Ahern, the Irish Prime Minister, and the Irish President, Mary McAleese, offered words of comfort, but there was nothing they could say to ease the pain.
Father Kevin Mullan, of the Church of Christ the King in Omagh, said he had worked through the night to counsel families and friends of the dead and injured. He gave the last rites to two people before they died. "I couldn't get over the number of dead. It was just awful," he said.
One man he comforted had lost three members of his family - his mother, sister and niece. "You just offer a shoulder to cry on and give them space to talk," he said. "You let them know they are not alone. You just cry with them."
He said families were being counselled when they came in to the Omagh Leisure Centre to try and establish details of missing friends and relatives. Those who it seemed had lost relatives were taken to a nearby army base where a makeshift morgue had been established.
One man whose brother had been blown apart told him: "Whatever is left I need to see it before he is buried. I need to see whatever is left, even just the bones. I need to say goodbye to whatever is there."
July 21 1972 Bloody Friday: 11 killed when IRA sets off 26 Belfast bombs.
October-November 1974 Mainland pub bombings kill 28. Loyalists kill 22 in Dublin.
February 17 1978 Twelve Protestants die in IRA fireball bomb at Ulster hotel.
August 27 1979 Warrenpoint: IRA bomb kills 18 soldiers.
October 1984 Brighton: Five die when IRA bombs Tory conference hotel.
November 1987 Enniskillen: 11 die in IRA Remembrance Day bombing.
February 1996 Docklands: IRA blows up South Quay station. Two die.
July 1998 Three children burn to death during Drumcree stand-off.Reuse content