MARBLEHEAD, MASS. (WHDH) - Approximately 1,000 customers lost power in Marblehead Thursday during a period of high heat in which temperatures reached nearly 100 degrees, Marblehead Municipal Light Deptartment General Manager Jon Blair announced. Shortly before 4 p.m., Blair said customers in the Lafayette Street and Humphrey Street areas lost power. He said the outage was not solely due to heat, but it was a contributing factor.