Sailing the Great Lakes: Lake Superior, Lake Michigan, Lake Huron, Lake Erie and Lake Ontario

Together the five lakes form the largest body of fresh water on earth. Lake Superior lies about 183 m above sea level, Lake Michigan and Lake Huron share the same level through the Straits of Mackinac, Lake Erie lies a little lower, and Lake Ontario about 100 m lower beyond Niagara Falls. They are linked by rivers and canals with locks: the Soo Locks on the St. Marys River, the St. Clair River, Lake St. Clair and the Detroit River, the Welland Canal with eight locks and finally the St. Lawrence River with the Seaway to Montréal.

Which sailing areas do the Great Lakes have?

Lake Superior is the coldest and loneliest of the lakes: clear water, high rocky shores and islands such as the Apostle Islands and Isle Royale, but long distances between harbours and water that rarely gets warmer than 15 °C even in August. The North Channel and Georgian Bay on the north shore of Lake Huron are considered the most beautiful cruising grounds of the lakes, with thousands of granite islands and sheltered anchorages. Lake Michigan has long sandy shores with harbours every 15 to 30 nm, on the east shore mostly behind narrow entrances into lakes. Lake Erie is shallow and warm, with the Erie Islands around Put-in-Bay as a holiday area. On Lake Ontario people sail from Toronto, Rochester and Kingston, and in the east the way leads to the Thousand Islands.

When is the best time to sail?

The season runs from mid May to mid October; most boats spend the winter ashore. July and August are the warmest months with the lightest winds, but with thunderstorms in the afternoon and evening. In June the water is still cold, and fog often forms on Lake Superior. From September the low pressure systems get stronger, and in October and November come the autumn storms of the lakes (the "Gales of November"), which have sunk even large freighters.

What makes sailing on the lakes special?

On fresh water the waves are short and steep: at just 20 kn a sea of 1.5 to 2 m with a short period builds over a long fetch, especially fast on shallow Lake Erie. Behind a cold front the wind often veers to northwest within minutes and freshens strongly. In summer thunderstorms move quickly across the lakes, with gusts above 40 kn. The water is cold even in summer, so falling overboard is more dangerous than at sea. The entrances of many harbours on Lake Michigan lie between piers in a river or lake behind them: in an onshore gale a breaking sea stands there.

How are water level and current calculated?

There is no tide. The level varies over the years and seasons by up to one metre, and on top of that there are seiches: strong wind pushes the water to one end of the lake, on Lake Erie up to 2 m between Toledo and Buffalo. Sailseer shows the NOAA gauges above the chart datum of the lakes (Low Water Datum), not above a tide. There is current only in the connecting rivers: up to 3 kn in the St. Clair River and the Detroit River, considerably more in the Niagara below Buffalo, and 1 to 2 kn in the St. Lawrence River at the Thousand Islands.

Which locks and canals are there?

Between Lake Superior and Lake Huron lie the Soo Locks at Sault Ste. Marie (USA, free of charge) and the small lock on the Canadian side. From Lake Erie into Lake Ontario the Welland Canal with eight locks leads around Niagara Falls (registration and fee with the St. Lawrence Seaway Management Corporation). From the lakes the Erie Canal runs at Oswego and Tonawanda to New York, the Trent-Severn Waterway from Georgian Bay to Trenton and the Rideau Canal from Kingston to Ottawa. Sailseer plans these waterways with locks, bridges and the operators' hours.

Which weather data does Sailseer use on the lakes?

The forecast comes from nine weather models, over the lakes with HRRR and HRDPS as regional models. The marine forecasts of the NWS (Nearshore Marine Forecast up to 5 nm, Open Lake Forecast for the open lakes) and of Environment Canada are shown verbatim along the route, together with the warnings of both services (Small Craft Advisory, Gale Warning). Measurements come from more than 100 buoys and coastal stations of the NDBC, the stations of Environment Canada, the NOAA gauges and the airports.

What applies at the border?

The border between the USA and Canada runs through all the lakes except Lake Michigan. Anyone who docks, anchors or goes ashore in the other country must report there: in the USA with the CBP ROAM app or at a reporting location (in person if you need an I-94, which means Europeans on their own boat), in Canada by phone from a CBSA telephone reporting site in a harbour. If you only pass through the neighbour's waters, you do not report. Sailseer shows the reporting locations along the route.