The Fort McMurray wildfire in northern Alberta continues to rage out of control, growing to more than 423,000 hectares. It is estimated that it might be early June before the tens of thousands of evacuated Fort McMurray residents would be allowed to return to the city.

Relief – in the form of cooler weather and slight precipitation – may be on the way for fire crews. The fire is now more than six times the size of Toronto with much of the fire’s growth confined to remote forested areas.

A risk modeling firm has estimated that insured losses could be between C$4.4bn (£2.3bn) and C$9bn (£4.8bn), although it warned officials it is still in the early stages to assess the total damage. The wildfire began southwest of Fort McMurray, Alberta, on 1 May and has spread ‘rapidly’ through forest, “quickly outpacing” local firefighters’ capacity to contain it.

A total of more than 2,400 structures have been lost as a result of the fire, which is around 10% of the total number of buildings in Fort McMurray. A mandatory evacuation notice and a state of local emergency were issued on 15 May for the Municipal District of Greenview.

Rating agencies are stating that the disaster had the potential to be the costliest catastrophic event in Canadian history.