I am not a fan of extended weather outlooks due to the inaccuracies of forecasting.
But... here's the 14 day forecast for Atikokan. Below average temps most of the time.
As an editorial: If I had a trip planned for the middle of May in Northern Q, I would just wait this out and see where we end up in a few more weeks. The sun's intensity is a larger player overall than the air temp in melting ice. So is wind.
And if I had a trip planned for mid May in the northern Q, I would also be nervous. I'm going into Beaverhouse June 8 and I'm a little nervous. Not a lot, a little.
Tom