© GLERLA freeze frame from the animation below showing one of the April 13, 2018 meteotsunamis in detail. Orange and red indicate a rising water level and blue shows a falling water level.
Meteotsunamis are a type of tsunami, but instead of being generated by an underwater earthquake, the source is meteorological, which gives them their unique name. Thunderstorms are the instigator for the development of many meteotsunamis because they sometimes provide the spike in wind speed and the atmospheric pressure change needed to trigger their formation.
On April 13, bands of thunderstorms pushing across northern Lake Michigan spurred the development of a pair of meteotsunamis.
NOAA's Great Lakes Environmental Research Laboratory (GLERL) released a modeling of the meteotsunamis in a tweet Friday. Click the play button below and notice rising water level (orange/red) followed by falling water level (blue) between 43 and 45 degrees north latitude (marked on the left side of the animation).
This happens twice in the same general area of the modeled output, indicating that the two separate meteotsunamis formed in response to storms that moved through the area.
"The meteotsunami was caused by those short, extreme bursts of wind and pressure," said the GLERL.
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