How cold is Lake Superior?

Today Lake Superior averages 47°F across its surface. It is the coldest of the Great Lakes, averaging only about 40°F through much of the year and peaking around 60–65°F in mid to late August. Shallow bays such as Chequamegon Bay and the harbors around the Apostle Islands warm up faster than open water.

Which Great Lake is the warmest?

Lake Erie, at 58°F today. Lake Erie is the shallowest Great Lake, so it warms fastest and often tops 75°F in August. Southern Lake Michigan and Lake Huron's Saginaw Bay are next; Lake Superior is the coldest.

When is the best time to swim in the Great Lakes?

Late July through early September. The lakes are slow to warm, so water in June is often 15°F colder than in August, and early September is frequently warmer than early July. Check the water and the waves before you go; conditions change quickly.

Why is the water at the beach colder than the forecast?

Lake averages hide big local swings. When the wind blows offshore it pushes warm surface water out and draws cold water up from the depths, a process called upwelling. Beach water can drop 15–20°F overnight. A nearby buoy reading, when available, is a better guide than the lake average.

Is it safe to swim in the Great Lakes?

Yes, with care. The biggest dangers are cold water and rip currents, which form near piers and breakwalls when waves reach about 3 feet. Most beaches have no lifeguards. Heed beach hazard statements and red flags, and if you're caught in a current, swim parallel to shore.

Water temperatures

How warm are the Great Lakes today?

Today's surface water temperature for all five lakes from NOAA satellite analysis, how it compares with normal, and a swim check for any beach on our map with the latest buoy readings, waves and alerts.

Lake-wide averages for Friday, November 13, 2026, from NOAA's Great Lakes Surface Environmental Analysis. Shallow bays and beaches can be much warmer or colder.

Lake Superior
47°F 8°C
+2.6°F warmer than normal
−0.9°F in the last week

5th warmest of 32 years
Dangerously cold
Lake Michigan
54°F 12°C
+5.6°F warmer than normal
−0.9°F in the last week

Warmest for the date in 32 years
Very cold
Lake Huron
52°F 11°C
+4°F warmer than normal
−1.8°F in the last week

Warmest for the date in 32 years
Very cold
Lake Erie
58°F 15°C
+6.3°F warmer than normal
−2°F in the last week

Warmest for the date in 32 years
Very cold
Lake Ontario
54°F 12°C
+5.4°F warmer than normal
−2.1°F in the last week

Warmest for the date in 32 years
Very cold

Swim check

Can you swim there today?

Pick a beach or town.

We'll check the nearest buoy for water temperature and waves, look for beach hazard statements, rip current and marine alerts, and give you a plain-language call.

Beach or town

Buoy readings are from the nearest station within about 40 miles on the same lake. Always follow posted flags and local advisories.

Dangerously coldBelow 50°F. Cold shock can leave a strong swimmer helpless within minutes. Stay out without a wetsuit.
Very cold50–59°F. Brief dips only. Cold shock is still a risk and hands go numb quickly.
Bracing60–69°F. Refreshing for a short swim; most people start to chill within half an hour.
Comfortable70°F and up. Comfortable for most swimmers. Waves and rip currents are now the main hazard.

Good to know

Great Lakes water temperature questions.

How cold is Lake Superior?: Today Lake Superior averages 47°F across its surface. It is the coldest of the Great Lakes, averaging only about 40°F through much of the year and peaking around 60–65°F in mid to late August. Shallow bays such as Chequamegon Bay and the harbors around the Apostle Islands warm up faster than open water.
Which Great Lake is the warmest?: Lake Erie, at 58°F today. Lake Erie is the shallowest Great Lake, so it warms fastest and often tops 75°F in August. Southern Lake Michigan and Lake Huron's Saginaw Bay are next; Lake Superior is the coldest.
When is the best time to swim in the Great Lakes?: Late July through early September. The lakes are slow to warm, so water in June is often 15°F colder than in August, and early September is frequently warmer than early July. Check the water and the waves before you go; conditions change quickly.
Why is the water at the beach colder than the forecast?: Lake averages hide big local swings. When the wind blows offshore it pushes warm surface water out and draws cold water up from the depths, a process called upwelling. Beach water can drop 15–20°F overnight. A nearby buoy reading, when available, is a better guide than the lake average.
Is it safe to swim in the Great Lakes?: Yes, with care. The biggest dangers are cold water and rip currents, which form near piers and breakwalls when waves reach about 3 feet. Most beaches have no lifeguards. Heed beach hazard statements and red flags, and if you're caught in a current, swim parallel to shore.

Lake temperatures: NOAA Great Lakes Environmental Research Laboratory, Great Lakes Surface Environmental Analysis (GLSEA), ranked against every year in its record for the same date. Buoys: NOAA National Data Buoy Center. Alerts: National Weather Service and Environment and Climate Change Canada. This is a guide, not a safety guarantee.

More planning tools: northern lights forecast, ship watcher, circle tour planner and the trip builder.

How warm are the Great Lakes today?

Lake Superior

Lake Michigan

Lake Huron

Lake Erie

Lake Ontario

Can you swim there today?

Pick a beach or town.

Great Lakes water temperature questions.