Justin Trudeau arrived almost two weeks after a wildfire ignited, tearing through the Alberta town and surrounding areas, causing several oil sands operations to shut down.
Alberta officials have said they will have a plan within two weeks for getting residents back into their homes, but also said that fire conditions were forecast to worsen.
Trudeau will meet with Alberta Premier Rachel Notley later today. His government has put together a special cabinet committee to co-ordinate Fort McMurray aid and reconstruction efforts.
More than 80,000 evacuees have begun receiving direct financial assistance from the Alberta government and the Canadian Red Cross as officials asked for patience in getting residents home.
Canadian Red Cross chief executive Conrad Sauve has said that each adult will receive USD 600 Canadian (USD 467) and each child will get USD 300 Canadian (USD 234) in what he called the most important and fastest direct cash transfer in the organization's history. It totals USD 50 million Canadian. (USD 39 million).