Lake Huron

Lake Huron - Cruising & Navigation

St. Clair River to the Straits of Mackinac

Lake Huron lies to the north of the western end of Lake Erie and is the second largest of the five Great Lakes by surface area. We will be avoiding the debate as to whether Lakes Huron and Michigan are actually a single lake, hydrologically speaking.

As with the other Great Lakes, except Lake Michigan, Lake Huron is controlled by both Canada and the United States with the international boundary running approximately down the middle of the main body of the lake from the head of the St. Clair River north to False De Tour Passage. While often disputed, North Channel and Georgian Bay are officially part of Lake Huron.

Chart of Lake Huron

Lake Huron is bordered on the north, east, and south by the Canadian Province of Ontario and on the west and south by the U.S. state of Michigan.

The primary water source of Lake Huron, is Lake Superior via the St. Marys River at its northern end. Waters from Lake Michigan also feed Lake Huron through the Straits of Mackinac, however the opposite is also true with the waters of Huron occasionally flowing into Lake Michigan. The lake’s outlet is the St. Clair River draining south through Lake St. Clair and the Detroit River into Lake Erie.

While Lake Huron has no direct navigational access to the Atlantic Ocean or Gulf of Mexico, it is connected by a number of means. Via the St. Lawrence River, Lake Ontario, and Lake Erie for deep draft vessels, via the Hudson River, Erie Canal, and Lake Erie for shallow draft vessels, and finally the Mississippi River System, Des Plaines River, the Chicago Sanitary Canal, and Lake Michigan when entering from the Gulf of Mexico for shallow draft vessels as well.

Lake Huron Facts
Lake Huron is ≈179 NM (206 SM / 332 KM) long and 159 NM (183 SM / 295 KM) wide at its widest point.



Navigable access to Lake Huron is limited to the St. Clair River, the St. Marys River, and Lake Michigan; all allowing passage for both deep and shallow draft vessels.

Navigation Season

For all vessels the navigation season is governed by ice on the lake. For commercial vessels and lock operations, the navigation season typically begins in late March (20th to the 31st) and runs through late December (24th to the 31st) typically being closed January, February, and a large portion of March.

For most recreational boaters, they typically launch in May and haul out by late October or early November.

Because of its depth, Lake Huron has never been known to completely freeze over in winter.

Buoys and Marks

Buoys, beacons, and lights on Lake Huron make use of the standard IALA Region B lateral buoyage system (Red Right Returning). In the Great Lakes, “Red Right Returning” is generally considered to be upbound.

Green Buoy Red Buoy

Buoy Guide

Lake Huron Facts
With a surface area of 23,007 mi² (59,590 km2 / 19,992.5 NM’s); Lake Huron is the second largest Great Lake (by surface area), slightly smaller than the state of West Virginia, and the 3rd largest freshwater lake in the world.

Charts Paper


The following NOAA Charts provide full coverage of Lake Huron’s U.S. waters from the head of the St. Clair River to Straits of Mackinac: #14860, #14862, #14863, 14864, #14865, #14867, #14869, #14881, and #14885

Chart #14860Covers the Entire Lake - Providing limited detail.

Chart #14862Port Huron, MI to Pte Aux Barques, MI - Covers the eastern shoreline of Michigan from Port Huron, MI north to Huron City, MI.

Chart #14865South End of Lake Huron – Covers from Port Huron, MI to Lakeport, MI.

Chart #14863Saginaw Bay - Covers the entire Saginaw Bay from Pte Aux Barques, MI around to Oscoda Au Sable, MI.

Chart #14864Harrisville to Forty Mile Point -Covers Harrisville, MI to Rogers City, MI.

Chart #14867Saginaw River - Covers Southern Saginaw Bay and the Saginaw River.

Chart #14869Presque Isle and Stoneport Harbor - Covers Thunder Bay, MI to North Bay, MI.

Chart #14881De Tour Passage to Waugoshance Point - Covers Forty Mile Point, MI to the Straits of Mackinac, MI

Chart #14885Le Cheneaux Islands - Covers from Rover Island, MI to Brulee Point, MI.


Canadian Hydrographic Service Charts provide coastal coverage from Sarnia, ON north to De Tour Passage, MI including Georgian Bay and North Channel.

Charts of Canadian waters are not available for viewing on line. However, the Canadian Chart Catalog does provide a general idea of the areas of coverage.

Listed below are Canadian Hydrographic Service Charts providing coastal coverage from the southern limits of Lake Huron north to the De Tour Passage and mid-lake to the western shoreline of Ontario (Georgian Bay).

CHS Chart #2228 - Southern Lake Huron

CHS Chart #2201 - Georgian Bay

CHS Chart #2207 - Little Current to Clapperton Island

CHS Chart #2244 - Alexander Passage to Beaverstone Bay

CHS Chart #2291 - Point Clark to South Hampton

CHS Chart #2297 - Duck Islands to DeTour Passage

CHS Chart #2235 - Cape Hurd to Lonely Island

CHS Chart #2242 - Giants Tomb Island to Franklin Island

CHS Chart #2243 - Bateau Island to Byng Inlet

CHS Chart #2245 - Beaverstone Bay to Lonely Island

CHS Chart #2251 - Meldrum Bay to St. Joseph Island

CHS Chart #2298 - Cove Island to Duck Islands

Many larger scale charts are available providing more detail of major harbors and constricted passages.

Lake Huron Facts
Lake Huron has a shoreline length of 1,850 SM’s (1607.6NM’s / 2,977 KM’s) plus an additional 1,980 (1720.6 NM’s / 3,186.5 KM’s) for islands in the lake.

Charts (Electronic)

The following electronic charts provide detailed coverage of all the Great Lakes from Montreal, CA on the St. Lawrence River to Duluth, MN on Lake Superior including: Green Bay, Saginaw Bay, Georgian Bay, Lac Nipissing, Lake St. Clair, Lake Simcoe, Seneca Lake, Cayuga Lake, Oneida Lake, Trent-Severn Waterway, Thousand Islands, the St. Lawrence River from Kingston to Montreal, the Ottawa River from the St. Lawrence River to Ottawa, Mohawk River, Rideau River, Welland Canal and Erie Canal.


Digital - Bluechart G2 Vision microSD™/SD™ card: VUS042R-Great Lakes


C-Map Max Chart NA-M026: Great Lakes, North East Coast & Appr. – All of the Great Lakes


Navionics Platinum+ 901P+: East Great Lakes – Ontario, Erie, and Huron
Navionics Platinum+ 900P+: West Great Lakes – Huron, Michigan, and Superior


Lake Huron is the fourth deepest of the (5) Great Lakes with the deepest section of the lake being in the Manitoulin Basin.

Other than the southern end of Lake Huron, the 5 fathom line (30 feet / 9.1 meters) can generally be found 2 NM offshore or less.

Lake Huron Facts
The average depth of the lake is 195 feet (32.5 fathoms or 59 meters). The deepest point being 750 feet (125.0 fathoms or 230 meters) located near 42˚30’48" N / 79˚53’20"W. Approximately 22.4. NM (25.8 SM / 41.5 KM) southwest of Tobermory, ON.

Lake the other Great Lakes, Huron's water levels also fluctuate with the seasons. Generally, the lowest lake levels are found in January and the highest in July, however exceptions to this have been noted. The average yearly level varies depending on long-term precipitation and snow melt off.

Major Lights

Below is a list of coast lights with a range equal to or greater than 10 SM. From the head of the St. Clair River north along the eastern shore of Michigan then east and south along the western shore of Ontario:

Ft. Gratiot Light
Fl G 6s 82ft 16 SM (13.9 NM/25.7 KM)

Port Sanliac Light
Fl 2.5s 69ft 14 SM (12.2 NM/22.5 KM)

Pte Aux Barques Light
Fl (2) 20s 93ft 16 SM (13.9 NM/25.7 KM)

Bay City Approach Light
Fl G 6s 50ft 10 SM (8.7 NM/16.1 KM)

Presque Isle Light
Fl 15s 123ft 22 SM (19.1 NM/35.4 KM)

Forty Mile Point Light
(Iso 6s 66ft 16 SM (13.9 NM/25.7 KM)

Cheboygan Light
Oc 4s 51ft 13 SM (11.3 NM/20.9 KM) HORN (MRASS)

Mackinac Island Light
Fl R 5s 71ft 11 SM (9.6 NM/17.7 KM) HORN (MRASS) RACON

Port Dolomite Light
Iso 6s 31ft 11 SM (9.6 NM/17.7 KM)

Martin Reef Light
Fl R 10s 65ft 13 SM (11.3 NM/20.9 KM) HORN

De Tour Reef Light
Fl 10s 74ft 15 SM (13.0 NM/24.1 KM) RACON HORN (MRASS)

Hope Island Light
Fl 5s 55ft 24 SM (20.8 NM/38.6 KM)

Gravelly Shoal Light
Fl R 6s 75ft 10 SM (8.7 NM/16.1 KM) HORN)

Tawas Light
Fl 4s 46ft 11 SM (9.6 NM/17.7 KM)

Thunder Bay Light
Fl G 10s 63ft 16 SM (13.9 NM/25.7 KM)

Middle Island Light
Fl 10s 78ft 14 SM (12.2 NM/22.5 KM)

Mississagi Strait Light
Iso 4s 46ft 15 SM (13.0 NM/24.1 KM)

Providence Bay Light
F 47ft 11 SM (9.6 NM/17.7 KM)

Cove Island Light
Fl 5s 101ft 18 SM (15.6 NM/28.9 KM)

Gereaux Island Light
Oc 10s 52ft 10 SM (8.7 NM/16.1 KM) RACON

Red Rock Light
Fl 7s 66ft 19 SM (16.5 NM/30.6 KM)

Cabot Head Light
Fl 10s 82ft 10 SM (8.7 NM/16.1 KM)

Western Islands Light
Fl 10s 74ft 10 SM (8.7 NM/16.1 KM)

Cape Croker Light
Iso 4s 61ft 15 SM (13.0 NM/24.1 KM)

Pt. Clark Light
Fl 10s 93ft 32 SM (27.8 NM/51.5 KM)

Distances and Mileages

Distances between major points on Lake Huron are listed below. The distances table is useful in planning overnight stops while transiting the lake and is available for download.

Lake Huron Distances Table

Distances are in Statute Miles

Points in this table are arranged in geographical sequence proceeding from St. Marys River southward along the west shore, and returning northward up the east shore, around Georgian Bay, and westward through North Channel.
(a) From foot of Grand River Avenue
(b) From sailing course point north of Old Mackinac Point
(c) From abreast east end of U.S. center pier and (except those colored ) via Middle Neebish and DeTour; distances downbound through West Neebish are 1 mile less
(d) Distances to Georgian Bay ports (except those colored ●) are via the bay entrance from Lake Huron and St. Marys River points and via Little Current from North Channel points
• Via False Detour and North Channels
• Via Mississagi Straight and North Channel
• Via Lake Nicolet, St. Joseph and North Channels
• Via Potagannissing Bay and North Channel

The above table can be downloaded for your personal and private use. The Lake Huron distance file contains the tables in Statute Miles, Nautical Miles, and Kilometers. The files are Zipped Adobe (.pdf) format.

Lake Huron Distance Table - View or Download

Lake Huron Facts
Lake Huron is the third largest Great Lake (by volume). With a fresh water volume of 859 SM3 (3,543 KM3), that works out to 9.45814 gallons or approximately 945.8 Trillion gallons.

Speed Limits

The speed limits on the open waters of Lake Huron can generally be considered to be unlimited except where posted or common sense prevails.

Transit Times

As a general guide, Port Huron to the Straits of Mackinac (245 SM / 212.9 NM / 394.3 KM) could be done in a little over 7.1 hours at 30 knots.

More realistically; with a SOG of 15 knots will probably require about 14.2 hours, 21.3 Hours at 10 knots, and 26.6 to 30.4 hours at typical trawler and sailboat speeds.

Tides and Currents


Studies show that the Great Lakes do in fact experience a semidiurnal tidal pattern. The tidal range however, is extremely small - averaging around 1 inch and reaching 1.6 to 2.0 inches (4-5cm) during the largest of tides. This tidal range is so small, that they are often hidden by other fluctuations in water levels that are caused by the weather. As a result, Lake Huron can be generally considered as "non-tidal."

Water Level Fluctuations

The normal elevation of the lake's surface does in fact change. During the course of each year, Lake Huron’s surface is subject to a consistent seasonal rise and fall, the lowest stages occurring primarily during the winter and the highest during the summer. These fluctuations generally average around 2.0 feet, but recently it appears that these fluctuations are getting larger while the general lake level is getting higher.

In addition to seasonal fluctuations, Seiches (changes in water level produced by winds, storms, squalls, and to a lesser degree, barometric pressure changes) often occur. The wind and barometric pressure changes that accompany squalls can produce fluctuations lasting from a few minutes to a few hours. Strong storm winds of sustained speed and direction can produce fluctuations lasting a few hours or a day. Lake Huron is less prone to these water surface oscillations than Lake Erie due to the lake’s surface area, north/south orientation, and deeper depths.

Surface Currents

Lake Huron’s surface currents are typically wind driven and tend to follow the wind direction. This implies that surface current tends to flow from the southwest to the northeast since the predominant wind direction on the lake is southwesterly. The only area where this may differ is in Georgian Bay and North Channel, where a ESE through south current flow may be found.

Average surface current speeds on Lake Huron during mid-summer are for all practical purposes non-existent. At its maximum, it rarely exceeds 0.6 knot and averages approximately 0.2 knots.


Like all of the individual Great Lakes, Lake Huron acts like heat sink that moderates the temperatures of the surrounding land, cooling the summers and warming the winters. The lake also acts like giant humidifier, increasing the moisture content of the air. In the winter, this moisture contributes to the heavy snowfalls famous for the Great Lakes area and known as "Lake Effect" snow.

The weather on Lake Huron averages from cool to mild during the months of May thru October.


Temperatures range from low to mid 60’s in May to upper 70’s during July and August before dropping back to the mid 50’s in October.

Water temperatures average between 39° F in May peaking out at approximately 69° F Late July and early August before dropping back into the mid 40’s by the end of October.


Wind speeds Average 11 MPH in May to 9 MPH in July and August increasing to 14 MPH during October.

The shape of Lake Huron is such that strong winds from any quarter may generate rough seas somewhere on the lake. South through west winds are common in early autumn, while west and southwest winds prevail in late autumn. West through northwest winds are often the strongest.

Summer winds blow mainly out of the south through west, particularly southwest. These directions are also favored during the other seasons. Gales, however, are encountered less than 1% of the time from May through September.

Wind speeds on Lake Huron of 15 knots or less occur on average 97.7% of the time during the summer boating season while wind speeds of 10 knots or less occur on average 86.9% of the time.

If the fetch and duration are sufficient, waves of 10 feet or more can be generated in open waters by winds from any direction once they reach 20 knots or more. This occurs most often during October, November, and December.

Gales are most frequent in autumn. By late summer there is a noticeable increase, lake wide, in the frequency of gales, and this increase until the end of the navigation season. During November and December, gales are blowing 5 to 10 percent of the time, while wind speeds of 28 knots or more may be encountered up to 23 percent of the time.

These winds are mainly generated by winter storms; their frequency falls dramatically in spring. By June and July, gales are expected less than 1 percent of the time, while wind of 28 knots or more blow less than 3 percent of the time. However, squall lines and thunderstorms can produce violent short period wind from spring through fall.

Lake Huron’s maximum wind occurred on November 11th 1913. Winds out of the south peaked at 78.2 knots (90 mph / 144.8 kph. These winds were triggered by the infamous Great Lakes Storm of 1913.

Shoreline extremes range from 43 to 53 knots. Directions of these extremes are often out of the southwest; but west, northwest, and northeast winds have set some of these records. Most of the records were set from late fall through late winter.


While visibilities are often restricted by any number of factors, fog is the most frequent and troublesome cause of reduced visibility on Lake Huron.

Dense fog plagues the mariner most often in spring and early summer over Lake Huron’s open lake waters. From April into July visibilities drop below 0.5 mile up to 11 percent of the time. May and June are the worst times, and the cold, central waters are the most likely place. These fogs are usually the result of warm air moving across the still cold lake. They often come on winds with a southerly component; but northwesterly, northeasterly, and easterly winds also bring them.

Fog is most prevalent and thickest during the morning hours. Rain, blowing snow and low clouds also reduce visibilities, particularly from late fall through early spring.


The orientation of Lake Huron make it susceptible to winds out of the northerly and southerly quadrants, which can quickly raise dangerous seas. If these winds are continuous over a long period of time, a surge problem (Seiches) can be created at both ends of the lake.

Rough seas are most frequent in late fall (November and December) and can occur most often anywhere on the lake. Waves of 9 feet or larger (3 m) can be expected less than 1% of the time annually.


While Thunderstorms can occur at any time, they are most frequent from April through October, with peak activity during June, July, and August. Over the open water during this peak season thunderstorms are encountered 2 percent of the time. They are most likely between midnight and sunrise. Onshore thunderstorms can be expected on 4 to 7 days per month in the summer months being most likely during the afternoons.


The central part of Lake Huron is mainly an open water area, but drifting patches of thin ice may be present from early February until mid-March. These patches drift S towards the St. Clair River.

Ice normally begins to form in harbors and shallow-water areas in early December with ice fields and concentrated brash forming in early January.

In North Channel, fast ice forms in mid-January and reaches a thickness of 25 to 30 inches by mid-March. In Georgian Bay, ice begins to form near the end of December, and fast ice is well established by early January. The cover spreads over the entire bay by the end of January. This ice usually reaches the thick category during the first half of March. Decay begins in mid-March; the ice melts within the bay, and the area is clear by mid-April. Rotting fast ice may be present in some areas until the end of April.

The Straits of Mackinac is subject to severe problem ice conditions. The area is very susceptible to wind actions, and the ice cover is unpredictable. Ice forms early in the season in the Straits and attains an average thickness of 17 inches and an average maximum thickness of 25 inches. The solid ice thickness remains about the same throughout the season. The prevailing W winds cause considerable ridging and 4 to 6 foot windrows are common. Some ice ridges as much as 30 feet deep have been reported.

Overall, ice deterioration begins in March or April, stable fast ice becomes drift ice moving with winds and currents. Tracks cut by icebreakers become unreliable as the ice field deteriorates and shifts. Thick shore ice may drift into otherwise open channels endangering even ice-reinforced vessels. A vessel which becomes beset in drift ice is vulnerable to grounding because of the many shoals, reefs and shallow-water areas in the Straits of Mackinac.

Boating Season Summary

May through October Average Occurances

Meteorological Table – Lake Huron
WX Element   May Jun Jul Aug Sep Oct   Annual
Wind > 33 Kts   0.5% 0.2% 0.2% 0.4% 1.2% 2.8%   1.6%
Seas > 9’   0.3% 0.1% 0.2% 0.2% 0.7% 1.5%   0.8%
Visibility < 2 NM   10.8% 10.4% 6.5% 5.3% 3.9% 3.3%   6.8%
Precipitation   7.8% 6.0% 4.8% 6.5% 8.6% 10.7%   10.2%
Temps > 69° F   1.3% 6.7% 21.7% 25.6% 6.7% 0.4%   7.8%
Mean Temps °F   47.3° 57.1° 65.7° 66.8° 59.9° 49.6°   52.1°
Temps ≤ 33° F   0.7% 0.1% 0.0% 0.0% 0.0% 0.9%   8.5%
Wind Direction   NW S S SW SW S   S
Thunderstorms   1.1% 1.8% 2.2% 2.3% 1.7% 0.7%   1.3%
Wind Speeds ≤ 15 Knots   94.5% 98.5% 99.2% 99.1% 98.2% 96.9%   ---
Wind Speeds ≤ 10 Knots   79.6% 89.0% 91.3% 90.5% 88.3% 82.5%   ---

Weather Radio

U.S. - NOAA Weather Radio

National Weather Service (NOAA Weather Radio) - Stations provide mariners with VHF-FM broadcasts of weather warnings, forecasts, radar reports and surface weather observations. Reception range is up to 40 miles from the antenna site, depending on the terrain, type of receiver and antenna used.

Lake Huron - NOAA Weather Radio
Call Sign Station Frequency Channel
WNG582 Sandusky, MI 162.450 MHz WX-5
WNG701 Bad Ax, MI 162.525 MHz WX-7
KXI33 West Branch, MI 162.550 MHz WX-1
KIG83 Alpena, MI 162.550 MHz WX-1
KIG74 Sault Ste. Marie, MI 162.550 MHz WX-1
WNG572 Emmet County, MI 162.475 MHz WX-3

Canadian Weather Radio (Environment Canada)

Environment Canada (Canada Weather Radio) - Stations provide mariners with basically the same type weather information as their counterpart; NOAA Weather Radio and making use of the same frequencies. VHF-FM broadcasts of weather warnings, forecasts, radar reports and surface weather observations. Reception range is up to 60 kilometers from the antenna site, depending on the terrain, type of receiver and antenna used.

Lake Huron - Canadian Weather Radio
Call Sign Station Frequency Channel
  Sarnia-Oil Springs, ON 162.400 MHz WX-2
  Goderich, ON 162.400 MHz WX-2
  Paisley, ON 162.550 MHz WX-1
  Rosseau, ON 162.550 MHz WX-1
  Orillia, ON 162.400 MHz WX-2
  Collingwood, ON 162.475 MHz WX-3
  Little Current, ON 162.475 MHz WX-3
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