Synopsis for Lake Superior .SYNOPSIS...A 29.1 inch low pressure over the Canadian Prairies will track toward Western Hudson Bay this weekend, passing a 29.7 inch trough across Lake Superior Saturday night. Weak ridging of 30.0 inches will track eastward across Lake Superior late Sunday ahead of a 29.7 inch trough that will cross Lake Superior Monday night. Ridging will build to 30.1 Tuesday into Wednesday. Synopsis for Lake Michigan .SYNOPSIS...High pressure of 30.3 inches over the Ohio Valley will shift to the New England coast Saturday while low pressure of 29.2 inches over Montana moves to Manitoba Saturday, and then near Hudson Bay Sunday deepening to 28.6 inches. A cold front will sweep across Lake Michigan Sunday. A trough averaging 29.6 inches will then move across the lake on Monday. Synopsis for Lake Huron .SYNOPSIS...High pressure, 30.20 inches, will continue to slide east into the Mid Atlantic through the evening. This high will then move off the East Coast tomorrow, allowing a cold front, 29.90 inches, to move through the Central Great Lakes Sunday night. Synopsis for Lake Erie .SYNOPSIS...High pressure 30.30 inches over West Virginia will drift eastward reaching the east coast by Saturday evening. A slow moving cold front will push east across lake Erie Sunday night into Monday followed by a reinforcing cold front on Tuesday. Synopsis for Lake Ontario .SYNOPSIS...A 30.4 inch high over the Mid Atlantic states will remain in place through Sunday. A cold front is then forecast to move into the Lower Great Lakes late Monday.