BUFFALO, N.Y. — When it comes to forecasting lake effect snow or afternoon cloud cover, a peek at Lake Erie’s surface water temperature is a must. If you want to enjoy a nice day on the lake, a check of the currents and marine forecast is a good idea. More often than not when we consider the lake, we just look at what we can see. But even though Lake Erie is the smallest and shallowest of the five Great Lakes, there is still a lot happening beneath the waves!
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The currents that we are most often concerned with are called “surface currents.” The “surface” can be thought of as the top 30 feet of water. At these depths, the wind is the primary driver of the way the water moves and how calm or agitated the lake surface is.
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All water below 30 feet is moving around in what observers call the “depth averaged current.” Lake Erie is as deep as 210 feet near the Long Point Escarpment. At these depths, wind isn’t “felt” because the energy from the wind gets absorbed by water at the surface. Instead, the current is shaped by Lake Erie’s bathymetry or the topography of the lake bottom as well as the shape of the shoreline.
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This depth averaged current tends to follow a similar pattern any time of the year, but there are definite differences between currents in the summer and currents in the late fall and early winter. Currents tend to be much weaker during the warm season and then quickly strengthen as colder air settles in for the long haul. Find out why by watching this week’s episode.
New episodes of Heather’s Weather Whys are posted to the WGRZ YouTube channel every Wednesday evening. If you have a weather question for Heather to answer, send it to her at heather.waldman@wgrz.com or connect with her on Facebook or Twitter.
