NOAA's National Weather Service Weather Forecast Office

View these two links for latest marine weather hazards (issued as needed): Hazardous Weather Outlook: See Marine Section Marine Weather Statement Special Marine Warning   General Information About Rip Current Hazards and Identification
If it's a buoy or a C-MAN station, dial it up using: Dial-A-Buoy!

Variety of Observed and Forecast Information from the
     Great Lakes Environmental Research Laboratory (GLERL)
Detailed Surface Water Temperature for Lake Michigan and Other Great Lakes
Great Lakes Surface Wind Analysis
Great Lakes Surface Data Plot
Great Lakes Water Levels - NOAA/NOS and U.S. Army Corps of Engineers
Great Lakes Ice Analysis - National Ice Center

• National NWS Marine Forecasts webpage
  

 Coded Port Forecast

• Entrance to Port of Milwaukee
• Green Bay Entrance Light and Sturgeon Bay Ship Canal Light
• Burns Harbor and Calumet Harbor

 Lake Michigan Nearshore Forecasts (within 5nm of shore)

• Milwaukee area from Winthrop Harbor, IL to Sheboygan, WI
• Green Bay area from Sheboygan, WI to Port Inland, MI
• Chicago area for Illinois and Indiana shores

• Lake Michigan

Marine Observations

 Current Weather For Western Great Lakes  South Shore Beach - Milwaukee (USGS Data)

 Real-time Meteorological Observation Network
(for southern half of Lake Michigan)

 Interactive Marine Observations
(current weather from active buoys and C-MAN sites)

• Western Great Lakes (Superior, Michigan)
• Eastern Great Lakes (Others)
• Interactive Marine Observations Main Page

Interesting Marine Info

 Guide to Sea State and Winds

 Bathymetry

• Lake Michigan
• Lake Superior