Few people are affected more by weather than the mariner. An unexpected change in winds, seas, or visibility can reduce the efficiency of marine operations and threaten the safety of a vessel and its crew. The National Weather Service (NWS), a part of the National Oceanic and Atmospheric Administration (NOAA), provides marine warnings and forecasts to serve all mariners who use the waters for livelihood or recreation.
The National Weather Service office in Chicago is responsible for the Lake Michigan forecast and the Nearshore Marine forecast for the Illinois and Indiana shores. We also issue warnings for short-term events like thunderstorms.
GREAT LAKES MARINE PORTAL
Official Graphical Wind and Waves Forecasts:
(Note: On Fridays this link may give Lake Michigan water levels. Lake level and temperature data are both sent out under OMRCHI.)