The commercial shipping season begins today (Wednesday) at the Twin Ports of Duluth and Superior. The Port Authority says the Roger Blough was scheduled to make an early morning trip to Two Harbors where iron ore pellets would be loaded. Four other Great Lakes freighters are expected to leave Superior or Duluth today (Wednesday) or early Thursday morning at the latest. The first foreign ships are expected on Sunday at the Twin Ports, after the Soo Locks open for the season early Saturday morning at Sault Sainte Marie.