Great Lakes Data add-on is based on the NOAA GLERL data and GLOFS data.
This add-on adds many new data points that show the greats lakes: water depth, water temps, currents, wind flow and forcasts. The add-on is setup so you can just look at one lake at a time, or one data type at a time.
Screen Shots of the add-on in use:
Click here to download.