National Weather Service Marquette MI
10:02 PM Wednesday April 25.
waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. occasional wave height is the average of the highest 1/10 of the wave spectrum. synopsis, a ridge of 30.0 inches will exit the upper great lakes overnight, followed by a weak trough of 29.8 inches on thursday. on friday, a low of 29.8 inches will track across the upper great lakes region. this low will track into quebec and merge with another area of low pressure, deepening to 29.3 inches on saturday. behind this low pressure system, high pressure of 30.0 inches will drop into the northern plains. by sunday, this high pressure will strengthen to 30.3 inches as it tracks across the region.