Is the Straits of Mackinac rough? What to expect on the crossing
Usually not. The ferry to Mackinac Island takes 16 minutes on a direct departure from either mainland dock, and Shepler's says wind and current play only a small role in the crossing time. The Coast Pilot says currents in the Straits are often strong and irregular, and that gales on neighboring Lake Huron are most frequent in autumn.
Crossing the Straits of Mackinac this week? Dizzout is drug-free sound therapy you can start in your seat on the crossing, with relief in about 90 seconds.Starts in your browser · works with any headphones
Stop seasickness. Get your personalized Dizzout plan. Paid subscription for full access.
On your phone? Scan to start there.
Strait · Northern Michigan · Reputation among passengers: mixed: commonly reported as uncomfortable in the wrong conditions.
- Low
- Moderate
- High
- Very high
Roughness summarises typical reported conditions for this crossing, not a forecast for any given sailing.
Irregular currents and autumn gales between two lakes
In the Nausea Index table of the 121 sea crossings we cover, the Straits of Mackinac is rated manageable, one of 81 in that band, with 40 rated higher. Full table: the roughest sea crossings, ranked.
Key facts
- The Straits of Mackinac is a strait, and passenger reports place it in the moderate roughness band.
- The mechanism behind that reputation: Irregular currents and autumn gales between two lakes.
- Conditions are reported roughest in January, February, March, November and December.
- The calmest months are usually May, June, July and August.
Why does the Straits of Mackinac get rough?
The Straits of Mackinac are the short waterway that connects Lake Michigan and Lake Huron, with a maximum depth of 295 feet. The Coast Pilot says currents in the Straits are often strong and irregular, and that wind-driven currents in the western Straits run eastward. Shepler's says wind, current and other natural factors play a small role in its 16 to 26 minute crossing time. On Lake Huron, which the Straits open onto, gales blow 5 to 10 percent of the time in November and December and less than 1 percent of the time in June and July.
When is the Straits of Mackinac roughest?
The Coast Pilot says gales on Lake Huron are most frequent in autumn: the frequency rises from late summer to the end of the navigation season, and in November and December gales blow 5 to 10 percent of the time. Their frequency falls dramatically in spring, and by June and July gales are expected less than 1 percent of the time. The Lake Michigan section rates October and November as the worst months for sea conditions on that lake, and the Straits are subject to severe problem ice conditions.
| Roughest water in Jan | Roughest water in Feb | Roughest water in Mar | Roughest water in Apr | Roughest water in May | Roughest water in Jun | Roughest water in Jul | Roughest water in Aug | Roughest water in Sep | Roughest water in Oct | Roughest water in Nov | Roughest water in Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Rough | Rough | Rough | Mixed | Calm | Calm | Calm | Calm | Mixed | Mixed | Rough | Rough |
Typical seasonal pattern, not a forecast. Any month can deliver a calm crossing or a bad one. Check the marine forecast for your sailing date. Select a month to see every sea and ferry crossing ranked for it.
Where to be on board
Front to back
- Bow (front)Avoid
- MidshipBest
- Stern (aft)OK
The crossing: 16 to 26 minutes
Roughest stretch: Mid-channel, away from the docks
Midship on a low deck, with a view of the island ahead. The ride is 16 to 26 minutes.
Get your read
A few quick questions about you, then your trip. Nothing is saved or sent.
Step 1: about you
How you usually react to travel is the single best signal. These come from the validated MSSQ.
Step 2: your trip
Pick the kind of trip you are planning.
Crossing the Straits of Mackinac? Have Dizzout ready
Stop seasickness
Dizzout is drug-free sound therapy you can start in your seat on the crossing, with relief in about 90 seconds. It plays precisely calibrated audio through any headphones you already own, wired or Bluetooth. Free to download.
Get your personalized Dizzout plan. Paid subscription for full access.
30,000+ travelers in 30+ countries · How we count
On your phone? Scan to start there.
Comparing apps first? See how the motion sickness apps compare
Not travelling yet? Remind me the day before my trip
Know someone who gets motion sick?
Send them the app that helps stop it, drug-free, in about 90 seconds, works with any headphones. Free to download.
The crossings that cross it
| Route | Typical duration | What to know |
|---|---|---|
| Mackinaw City to Mackinac Island (Shepler's) | about 16 minutes direct, about 25 minutes on a Mighty Mac departure | Mighty Mac departures go under the Mackinac Bridge and take about 10 minutes longer. |
| St. Ignace to Mackinac Island (Shepler's) | about 16 minutes direct | Shepler's lists the same 16 minutes for direct departures from St. Ignace and Mackinaw City. |
What helps on this crossing
- Choose a direct departure if you want the shortest ride. Shepler's lists 16 minutes direct, and the Mighty Mac departure under the bridge takes about 10 minutes longer.
- For the calmest water, go in late spring or summer. The Coast Pilot says gales on Lake Huron are expected less than 1 percent of the time in June and July.
- Sit midship on a low deck, keep your eyes on the horizon and put your phone away.
For the full toolkit see the seasickness guide, or what to do once it has already started. For what the trials actually say about the oldest trick on that list, see the verdict on looking at the horizon. If the rocking follows you ashore afterwards, that is land sickness, which is normal, and it passes.
Frequently asked questions
Is the Straits of Mackinac rough in July?
July is one of the calmest months. The Coast Pilot says that by June and July gales on Lake Huron are expected less than 1 percent of the time. Squall lines and thunderstorms can still produce violent winds from spring through fall. The crossing to Mackinac Island is 16 minutes direct.
Is the Straits of Mackinac rough in October?
October is mixed. The Coast Pilot says gales on Lake Huron are most frequent in autumn, and that their frequency climbs from late summer until the end of the navigation season. For Lake Michigan, it says sea conditions are worst in October and November.
Is the Mackinac Island ferry rough?
It is a short ride. Shepler's lists 16 minutes for a direct departure from either Mackinaw City or St. Ignace, and says wind, current and other natural factors play a small role in travel time. The Coast Pilot says currents in the Straits are often strong and irregular.
What makes the Straits of Mackinac choppy?
Wind and current. The Straits connect Lake Michigan and Lake Huron, which are hydrologically one body of water. The Coast Pilot says currents in the Straits are often strong and irregular, and that wind-driven currents in the western Straits run eastward.
Is the Straits of Mackinac rough in winter?
Usually, yes. In a typical year, December, January and February are all rated rough. This is the typical pattern, not a forecast for any sailing.
Other crossings
Sources & further reading
- https://www.sheplersferry.com/faq
- https://nauticalcharts.noaa.gov/publications/coast-pilot/files/cp6/CPB6_C10_WEB.pdf
- https://nauticalcharts.noaa.gov/publications/coast-pilot/files/cp6/CPB6_C11_WEB.pdf
- https://en.wikipedia.org/wiki/Straits_of_Mackinac
- https://www.ndbc.noaa.gov/station_page.php?station=45175
Sea conditions described here are typical patterns drawn from published marine and operator information as of July 2026, not a forecast: conditions on any given sailing depend on the weather that day, and any month can deliver a calm crossing or a bad one. Route and operator names are trademarks of their respective owners; Dizzout is not affiliated with or endorsed by them. Seasickness sensitivity varies from person to person; this page is informational and not medical advice.