At five in the morning, there’s water in the streets of Nazaré. Dark and swirled with sand, it comes racing across the wide beach and into the town square, wetting the shoes of late-night revelers and lapping against the monument to the mulhers, the long-suffering women of this ancient Portuguese fishing village. You can’t see the waves yet, but the surf roars like a 747, echoing off the cliffs to the north. Big Mama is here.