Buoy Data - includes also information like wave height, wind direction, water (surface) and air temperatures is provided, but more advanced buoys are being deployed that can give biological or chemical information.
Eastern Great Lakes Buoy Data - Covers Lake Huron, Lake Erie and Lake Ontario
Western Great Lakes Buoy Data - covers Lake Superior and Lake Michigan
Web-based tools for weather and water:
Michigan Enviro-Weather - a graphical tool for displaying current and historic weather data specific to this region (temperature and rainfall, soil conditions, degree day data and comparisons, and forecasts)
National Snow Analyses - raw data and 2- and 3-D maps of snow from NOAA; includes snow depth, snow-water equivalents, snow melt, surface sublimation, and non-snow precipitation; use tools to zoom and display near-realtime data
National Weather Service - useful for radar and forecasts for the entire US, including maritime forecasts