An 80 mph wind gust was recorded at the Lighthouse at Michigan City, Indiana Tuesday evening. The above pic. from the lighthouse looks back toward shore about the time of the strongest gust. Here’s two pictures below of Lake Michigan at Michigan City, Indiana…one before the strong wind and the other 1/2 hour after the first pic. and after the 80 mph gust:
Above is the first pic. taken at 7:34 EDT PM. The wind here is from the south ahead of the storm. It’s offshore and the lake is pretty flat. You can see a bit of sunshine to the left and the storm approaching on the right side of the pic. The small waves would be “moving” from south to north with the prevailing wind.
This picture was taken 1/2 hour later. The peak gust of 80 mph here at the lighthouse as occurred. The waves are now coming from the NNW and there are whitecaps. At 7:40 EDT, the wind at the buoy was south at 8 pm. At 7 pm, the wind was NNE at 29 mph gusting to 49 mph.
Note…it’s not raining yet…the strong winds have gone out ahead of the rain. When we show you radar, 99% of the time we’re showing base reflectivity. The radar sends out a (pulsed) signal. When that signal hits a solid object, a portion of the signal is reflected back to the radar. We can measure the amount of time it takes for the radar impulse to return to the station to see how far away the rain is located. We can also measure the amount of signal that returns to determine the intensity of the precipitation. If there is just wind and no rain, the radar won’t show anything.
Remember, a strong thunderstorm may have its strongest winds ahead of the start of the rain on radar.
The pic. above is from the Michigan City buoy, about 3 miles offshore, looking south at 6 pm CDT (8/24/21). The sky doesn’t look threatening. The waves would be a little higher here than at the shore with a south wind. The waves here were running 8″ to a foot when the pic. was taken.
This picture is one hour later, at 7 pm CDT. Note the flash of lighting in the distance as we face to the west. The wind has come up from the NW-N blowing out ahead of the storm.
This pic. is from the Michigan City buoy at 8 pm – one hour later. The light is from lightning. It’s raining fairly hard and the rain makes it hard to see individual strokes of lightning – the sky just generally gets light for a second.
Look at the sea billows roll. Imagine you’re the captain of a sailing ship in the 1800s at 6 pm sailing across the lake (yeah, no motor). There’s no weather forecast from radio or your phone. How perceptive would or could you be at 6 pm to get out of harm’s way. Note how quickly the waves build on the lake. By 7:40 local time, waves were running as high as 6 feet at the buoy. I sure wouldn’t have wanted to be out there in my kayak. BTW – always wear or have next to you your floatation device. I never kayak – not even in 3 foot deep water – without my life jacket on.
ALSO: Two rescued after sailboats capsize on Lake Michigan. A total of eight overturned boats were found in the water and along the beachfront.
One more thing. Whenever we have thunderstorms with strong winds, beware of a seiche or meteotsunami. The strong wind can push the water toward the Michigan shore, where the water level will rise (and can rise as much as several feet!). Then as the storm passes and the wind dies down, the water retreats and as it does, strong rip currents and structural currents (along the piers) will develop. These currents can drag you back out toward the middle of the lake. After a windy thunderstorm, it’s best to stay out of Lake Michigan for a few hours until we know that the water level has stabilized.