More than 100 years ago the Weather Service charted prevailing currents in all of the Great Lakes. Personal observation and informal discussions among GLCC members have confirmed the validity of those charts today. Prevailing winds and outflow of water to the ocean effect these systems. Where currents exist their speed can reach from one to as much as four knots, more than sufficient to influence both passage times and fuel economy.

Experienced Great Lakes sailor, Niels Jensen, will explain the prevailing currents in each of the five great lakes. Boaters engaging in long-distance Great Lakes cruising, as well as sailboat racing, will find the current charts of particular interest. In addition to their affect on passage times, Niels will examine how currents also interact with winds to create certain wave phenomena. The best known of these is the wind-against-current situation, which can quickly generate dangerous conditions that, for the comfort and safety of their crew, captains of small recreational craft should well understand.