Earl's huge size means hurricane-force winds and storm surges will be a problem even if, as forecasters predict, it doesn't make landfall in the U.S. and stays off the coast. Canada, on the other hand, is increasingly confident the storm will hit sparsely populated southern Nova Scotia on Saturday morning.

"Landfall of Earl may occur in vicinity of Western Nova Scotia to the Fundy coast of New Brunswick early Saturday morning," Environment Canada reported Thursday. "The details of the public impacts will be assessed further later today and tonight."