National Weather Service Marquette MI
9:51 PM Friday August 18.
occasional wave height is the average of the highest 1/10 of the wave spectrum. synopsis, low pressure of 29.6 inches will track across southwest quebec tonight. high pressure of 29.9 inches will reach the western great lakes and then expand southward over the ohio river valley saturday into sunday. on sunday afternoon a 29.8 inch trough moves into western lake superior and then tracks east through sunday night. this trough will linger over the upper great lakes through monday and move over the eastern great lakes tuesday. a 30.0 inch area of high pressure will drop south across the upper mississippi valley on tuesday. 30.2 inch high pressure over the canadian prairies tuesday morning will reach the western great lakes by wednesday evening.