Synopsis for Lake Superior .SYNOPSIS...Weak high pressure of 30.1 inches will set up over the western Great Lakes today. A weak low pressure trough of 30.0 inches will then drop south across Lake Superior late tonight and Wednesday morning. As the trough dissipates Wednesday, high pressure of 30.2 inches will build over the Great Lakes region. The high will drift toward the Mid-Atlantic States on Thursday as one low pressure trough of 29.7 inches drops across far northern Ontario and a second trough of 29.7 inches emerges over the western Plains. Both troughs will move closer to the Upper Great Lakes on Friday, then converge over the Upper Great Lakes on Saturday. Synopsis for Lake Michigan .SYNOPSIS...Low pressure of 30.0 inches will move across the eastern Great Lakes tonight. High pressure of 30.1 inches will build over the western Great Lakes today and shift to the eastern lakes by Thursday then to the mid Atlantic Coast Thursday night. Low pressure of 29.6 inches will move from Manitoba Thursday night into the Upper Midwest Saturday night while it fills. Synopsis for Lake Huron .SYNOPSIS...Low pressure, 30.00 inches, will move from southern Lower Michigan this morning to Lake Erie this afternoon. High pressure, 30.10 inches, will then push into Lower Michigan from the west tonight. This high will expand across the Great Lakes region by Wednesday, strengthening to 30.20 inches. This high will gradually drift off to the Mid Atlantic Thursday into Friday. A slow moving front is then forecast to push into the region from the north on Saturday. Synopsis for Lake Erie .SYNOPSIS...A weak low pressure system 29.90 inches near western Lake Erie will move east today dragging a weak cold front across the lake. High pressure 30.20 inches will move east across the lake Wednesday into Thursday and move off the east coast on Friday. A warm front will develop over the midwest and move north near Lake Erie by Saturday. Synopsis for Lake Ontario .SYNOPSIS... A weak 30.0 inch low will move across New York State today. A 30.1 inch high will then build into the Great Lakes Wednesday and Thursday before drifting off the southern New England coast Friday.