Boatnerd Discussion Forum

Water depths are an issue because the water is so deep. The Joe Block probably has 5 shots of anchor chain. In normal conditions you put down a ratio of 4 or 5 to one as recommended by Bowdich, Duttons and AMSM. That means for every foot of water at least 4 (or 5) feet of chain goes out. More goes out in bad weather to insure you have a good purchase and don't drag the anchor. So, in good weather, with 5 shots, you have to find a spot that is less than 90' deep. Thunder Bay is generaly pretty deep, the upper corner is an area with less depth to the water and thus a popular ancorage.

When I first saw her, according to the AIS map location, she was on the N side of Caribou Is. in TB. I pretty much figured she was in the bay for impending weather but hadn't seen anyone go up quite that far. Water depths weren't a problem abviously. Thanks to all for sharing info. and the map.

link to online version of US chart 14968 [url]http://www.charts.noaa.gov/OnLineViewer/14968.shtml[/url]

Thunder Bay, Ont. has deep water until you get in close to the beach. If you have a chance to look at a chart (14968) you will see where the water is. It will also give an indication of the bottom conditions. That will explain it better than I can. Anyway, Thunder Bay is good shelter, but due to general depth the places that are good for anchorage can be limited. Up in the corner is a etter one. Also, if you are hiding from north wind the closer you are to the windward shore the better.

Try this link for a really neat wind flow chart centered on northern Michigan.

http://www.iwindsurf.com/windandwhere.iws?regionID=99&regionProductID=3&day=0&timeoffset=2&selected_model_id=

Use the pulldown on the left side to set it for the entire Great Lakes area (last choice, the bottom of the list) Note that the default time setting is a few hours into the future, you can select various times so I set it back as close to the current time as possible for actual winds.

I really like the wind-flow diagrams as they give a good idea of where the lows or highs are. You can see the winds swirling around the focal point, and both the length of the wind lines and the colors make it easy to see the winds. Switch back and forth from this chart to the AIS and you get a good idea of why the freighters are anchored.

I too use weather.com but to get an overall view, I use intellicast.com. Current > winds and then click on the general area where you want to see the details.

I've seen footers go to anchor in the same spot so it must be pretty protective. Virtually anyime boats go to anchor it's due to wind. I used weather.com and entered Thunder Bay which gave the same forecast for winds. In the western great lakes today winds are SSW and quite gusty, over 30mph.

I see 30 kt winds from the SW forecast, and building later. I am surprised to see the Block up at that end of the bay, I would think it would tuck down in the other end. Maybe there is something small they can hide behind.
I noticed the other day that the Block was stopped very close to the shore east of Superior. I watched it online sitting there, and then it finally turned and headed up towards Two Harbors. The winds were out of the south so maybe it was anchored while waiting for a loading dock.
I use a wind-surfing website to view the wind direction and speed around the lakes, it helps to explain many questions about anchored vessels.

I noticed on a map that the JLB was tucked way up in Thunder Bay in Lake Superior. I know they drop the hook up there in bad weather but she is up there about as far as a vessel can go. Is the weather bad in the area? Any news why? TIA