Cold water worries: A danger of Lake Michigan in spring
KALAMAZOO, Mich. — Two brothers tragically lost their lives on Sunday at Warren Dunes State Park. Authorities confirmed the teens started struggling when they reached a point too deep for their feet to touch the sand.
Making matters more difficult, investigators said water 3 feet down was in the 50s, while shallow water along the shoreline was in the lower 60s.
According to resources from the National Weather Service, cold water drains body heat four times faster than cold air. While 55 degree water may not sound that cold, it can be deadly.
Water temperatures in the 50s or below are cold enough to induce something referred to as "cold shock", especially if you quickly enter the water by jumping or falling in.
Cold shock refers to your body's natural instinct to tense up in the event you're submerged in cold water. It can cause a sudden spike in heart rate and blood pressure, and within minutes the average person can begin to lose some muscular control.
Cold shock is something to also consider on our many inland lakes and rivers. When boating or paddling on the water, always wear a life jacket and dress for the water temperature instead of the air temperature.
Lake Michigan water temperatures
Despite our recent warm up, water temperatures on Lake Michigan remain too cold to swim by most people's standards.
In another month or so, water along West Michigan beaches is likely to be much more tolerable. Warmer air temperatures and a more direct sun angle help to warm up the big lake as we head into summer.
Lake Michigan sees its warmest water temperatures typically from late-June through mid-September. It's not uncommon to have surface water temperatures in the 70s and sometimes even low 80s along the West Michigan lakeshore in that same time frame.
The graph above represents long-term averages. It's important to note that water temperatures can rapidly change, sometimes in a matter of hours.
How it's measured
Lake Michigan surface water temperatures are measured by buoys and by weather satellites.
Two fixed offshore buoys along the West Michigan shoreline provide weather and water data in real time. One is located near South Haven, while the other is near Port Sheldon.
Fixed buoys are anchored to the bottom of the lake. For the buoy in South Haven, that's about 66 feet deep.
Temperature sensors on the buoy's tether provide a vertical temperature profile of the water. The "surface" water temperature is technically measured 1 meter below the water's actual surface, with deeper water much colder.
Where to find buoy information
At News Channel 3, we report water temperatures and swimming forecasts throughout the summer months. If you'd like to access the data for yourself, there are several online platforms to find it.
- NOAA's National Data Buoy Center
- Great Lakes Observing System Seagull platform
- South Haven's beach flag status homepage
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