A downpour flooded streets in several neighbourhoods across Fort McMurray, the northern Alberta community where residents have only recently begun returning to their homes weeks after being forced out by wildfire.

Rain pounded the city all day Thursday — a total of 47 millimetres — flooding several neighbourhoods, including Thickwood and Timberlea.

Alberta Agriculture and Forestry said in a release the "rain has increased the hazardous conditions within the Horse River Wildfire."

It warned people to stay away from burned areas as trees could come down.

It was just last week that the 80,000 people living in Fort McMurray were allowed to return home after a wildfire forced the evacuation of the city on May 3.

Stroud Bay in the Thickwood neighbourhood was one of the areas of Fort McMurray affected by flooding from a downpour. (Tina Pilgrim)

Stressful memories

While some welcomed the rain, it brought back stressful memories of the summer of 2013 for Thomas Jackson.

After a deluge of heavy rains that June, the Hangingstone River overran its banks and flooded parts of Waterways, Grayling Terrace, and the downtown core.

"We've had rain like this before, but I haven't seen flooding like that since 2013 when we had that last major flood up here," said Jackson.

"It's not at that level yet, but I haven't seen the sewers back up like this before. The water is getting pretty high, up to the top of people's bumpers."

Welcome the rain was. But maybe the flooding in the condo parade will recede by the morning. <a href="https://twitter.com/hashtag/ymm?src=hash">#ymm</a> <a href="https://twitter.com/hashtag/waterworld?src=hash">#waterworld</a> —@IanInTheMac

Jackson said Thursday that vacuum trucks have been parked in neighbourhoods around the city all day, pumping out the overworked drainage lines.

Earlier in the day on several streets in some of the worst-hit areas, bylaw officers were knocking on doors, Jackson says, asking residents to check their basements for signs of flooding.

"The rain was good at first because everybody was hoping for rain, and now I think it's going to start worrying people again. I mean, they come back from being evacuated, and now they have something else to deal with."