A powerful cold front is, quite literally, blowing through the eastern US currently. While this front incites severe weather in the south, it’s facilitating a phenomenon not seen terribly often a bit further north.
Western winds, gusting to around 60 mph over the open waters of Lakes Erie and Ontario, are creating an event known as a Seiche.
Some of you may remember that I covered this topic in November 2020. For those that don’t, here’s a quick explainer:
A Seiche works a bit like storm surge, except that it isn’t associated with a tropical cyclone. Powerful winds blow across the length of the Great Lakes, unimpeded by friction out over the open water. These winds then create larger-than-average waves while essentially pushing the water in the basin to the opposite side. The result is low water levels upwind and higher water levels downwind. Oftentimes, these water levels are high enough on the downwind side that they spill over onto the shores of the lakes, flooding near by properties.
But winds don’t last forever. Once they abate, the excess water piled up downwind will rush back to the opposite side of the lake, creating a sloshing effect. The water then oscillates back and forth until equilibrium is achieved – much like water sloshing in a bathtub, just on a larger scale.
So, with this current western wind, the eastern shores of both Lake Erie and Lake Ontario are under Lakeshore Flood Advisories.
Fortunately, however, this isn’t a long-lived event. It’s expected to end this evening with a wind shift as the cold front passes east. But just because it isn’t long lived doesn’t mean it isn’t impactful. Gusts approaching 60 mph near the shores could be damaging. Any flooding that occurs also isn’t ideal.
Also, large, wind-driven waves could make travel on the lakes near impossible.
Personally, with waves of 10 feet (or maybe more) possible, I certainly wouldn’t be out on the water for any reason.
So, not a particularly long-lived event or as impactful as it could be. However, hopefully some of you learned something new today and can recognize this type of event next time it occurs!