Officer McDonald was shot and killed last Tuesday while pursuing a suspect. He is the fourth Philadelphia police officer to die in the line of duty in the past 11 months.
The viewing will take place until 11 o'clock.
Officer McDonald's funeral mass will be celebrated at the Cathedral Basilica at noon by Cardinal Justin Rigali.
A long blue line stretched into the Givnish Funeral Home in the Northeast Monday night for the first viewing for Officer McDonald.
It was a difficult night as friends, family and collegues paid their respects.
Residents lined the streets and the viewing line wrapped around two blocks for several hours.
"You come here to support police officers and firefighters and, you know, the guy gave his life in the line of duty," said Bill Hardiman of Northeast Philadelphia.
"Very sad. I've lived here all my life and I haven't seen this many ceremonies as in the past year," said Mary Beth Scary of Northeast Philadelphia.
The pain was clear on the faces of the men and women in blue who were led in a procession by Police Comissioner Charles Ramsey.
Just after 5:00 p.m., they marched from McDonald's alma mater, Archbishop Ryan, to the front of the Givnish Funeral Home where they were met by McDonald's family and girlfriend of four years, who is a police officer herself.
"It's a difficult day, but it's even more difficult for the family," said Police Commissioner Charles Ramsey. "Right now I'm focused on them and making sure they have what they need."
Behind the procession of police officers were members of the Arch Bishop Ryan football team. McDonald, a 1996 graduate, played for the school.
His coach called him Mr. Intensity. The 30-year-old was said to be fiercely dedicated to athletics, his family and the force.
McDonald's partner Richard Bowes, who was shot in the hip, was at the viewing. He received a round of applause when he left the funeral home.
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