Synopsis for Lake Superior .SYNOPSIS...A 30.2 inch high pressure centered over the Central Appalachians tonight will reach the East Coast Wednesday morning. A 29.4 inch trough across the Northern Plains tonight will drift across Lake Superior Wednesday afternoon into Thursday. A 29.6 inch trough will then linger over the Upper Great Lakes into Saturday night. The trough will lift to the northeast on Sunday ahead of a 30.1 inch ridge building across the Upper Mississippi Valley. Synopsis for Lake Michigan .SYNOPSIS...A 30.1 inch high over the Ohio Valley will continue east and reach the mid Atlantic coast Wednesday afternoon. A 29.4 inch low over southern Saskatchewan will expand south and form a 29.5 inch low over Minnesota Wednesday evening. The low will stall over Lake Superior early Thursday morning, and then reach Quebec early Friday morning. Its cold front will pass over the lake Thursday. A second low will form over the southern plains early Thursday morning, and it will pass over the lake at 29.7 inches Friday. Synopsis for Lake Huron .SYNOPSIS...High pressure...averaging 30.10 inches...centered over the Ohio Valley will continue to expand across the region tonight. This high will then drift east on Wednesday, as the next low pressure lifts out of the northern plains. This low...averaging 29.60 inches... will then track through the northern Great Lakes on Thursday. Synopsis for Lake Erie .SYNOPSIS...High pressure 30.10 inches will move across the Ohio Valley tonight, reaching the East Coast late Wednesday. A warm front will develop over the Mississippi Valley and move northeast across the Great Lakes Wednesday night into Thursday. Low pressure 29.60 inches from the northern Plains will reach the central Great Lakes Friday and bring a cold front to near the lake. The next low 29.70 inches will move northeast across the western lakes and take the cold front across Lake Erie Saturday. Synopsis for Lake Ontario .SYNOPSIS...A surface high will drift across the Ohio Valley overnight and then move off the Mid Atlantic Coast on Wednesday. Then a 29.5 inch low will slowly cross the Upper Great Lakes Wednesday night and Thursday. This low will push a a warm front across the lake Thursday...with the front oscillating back and forth over the region Friday and Saturday. Then a weak 30.0 inch high is forecast to develop near Indiana on Sunday.