Granite Island, MI (GRIM4) — Live Marine Conditions & Buoy Data
NOAA station GRIM4, Granite Island, MI, reports real-time marine conditions from 46.721°N, 87.412°W in Lake Superior (Michigan). Readings refresh roughly every 10 minutes, and Big Buoy adds a solunar table and a multi-day weather outlook for the area.
Lake Superior Marine Conditions — Granite Island, MI is one of several stations in Lake Superior. See live buoy data and solunar for the whole area.
What NOAA buoy GRIM4 measures
Station GRIM4 does not report a full meteorological suite; Big Buoy shows the observations available at this location and pairs it with the nearest offshore buoy so you still get a complete picture of the area.
What to watch in Lake Superior
Lake Superior is the coldest, deepest, and largest of the Great Lakes, with enough open water and fetch to build true offshore seas. Water stays cold most of the year and storms move through fast, so a sustained blow can raise steep, short-period waves with little warning — read wind, fetch, and sea state together before heading out.
Frequently asked questions
- Where is NOAA buoy GRIM4 located?
- Granite Island, MI (GRIM4) reports from 46.721°N, 87.412°W in Lake Superior (Michigan).
- How often is NOAA buoy GRIM4 updated?
- Station GRIM4 typically reports new observations about every 10 minutes. Big Buoy refreshes continuously so you always see the latest readings, alongside a solunar table for the area.
- What does NOAA buoy GRIM4 measure?
- Big Buoy shows the observations available at this location, plus the nearest offshore buoy for Granite Island, MI, plus solunar peak windows and a multi-day weather outlook.
- Is Big Buoy free to use?
- Yes. Live data for Granite Island, MI and every other NOAA buoy is free with no account required. Big Buoy Pro adds the Wind Tab, the Depth Chart, satellite overlays (sea surface temp, chlorophyll, currents), 16-day forecasts, and forecast model switching.