Great Lakes Water Levels - UPDATED 6/4/2019

According to the US Army Corps of Engineers, June report, precipitation across the Great Lakes was above normal during the Month of May.  Lake Erie saw an additional rise in lake levels.  Provisional data places the average May Lake Erie water level above the previous record from 1986 by 3 inches.  Read their full June report here.

The National Weather Service issues Lake Shore Flood Warnings when short-term coastal impacts are expected via a Lakeshore Hazard Message (note: this is s shared product with the Coastal Hazard Message for beach hazards). 

Current Lake Erie Water Levels (Toledo, Marblehead, Cleveland, Fairport, and Erie PA)

The National Weather Service works closely with local emergency managers to relay impacts from the lakeshore flooding.  Impacts from the high water can also be relayed to the NWS Cleveland office via email (nwscle@noaa.gov) or through facebook.com/NWSCleveland and twitter.com/NWSCLE.

Great Lakes Water Levels - 5/11/2019

Water levels fluctuate on seasonal, monthly, and daily time scales.  Seasonal and monthly water level averages are driven by the amount of water flowing into and out of the Great Lakes (via precipitation into the lakes or surrounding watersheds or evaporation). The monthly average water level on Lake Erie for 2019 is now nearing record levels set in May of 1986.

This spring has brought very saturated conditions to much of the Great Lakes region. According to the US Army Corps of Engineers May report, precipitation across the Lake Erie basin was at 137% of average for April. Lake Erie is forecast to reach it’s annual peak during the month of May.  Lake Erie, however, is predicted to fall 3 to 6 inches below record high from June to September, and 15 inches below in October.

Meteorological Set Up for High Water on Western Lake Erie

On time scales of days or even hours, meteorological conditions can lead to locally varying water levels. This can pose a threat to life and property from lakeshore flooding and beach and shore erosion.

A particularly vulnerable location is the western lakeshore of Lake Erie.  Here, sustained winds of an east or northeast direction can create a seiche to develop.  A seiche is a rise of water in large lakes that is created as a result of strong winds and/or large barometric pressure gradient. The lake acts like a giant bathtub where water can be pushed to one side with lower water levels on the opposite side.  In an extreme case, water levels between Toledo and Buffalo can differ by more than 10 feet.

The below image shows an example of the type of weather pattern that leads to a high water scenario on the western basin of Lake Erie. The map shows strong easterly winds between high pressure located north of the lakes and low pressure approaching from the Plains.

Surface analysis for Wed May 8 2019 at 18Z showing conditions that lead to high water on Lake Erie

Lakeshore Flood Warnings and Flooding Impacts

Recently, the combination of the lake level running above normal and elevated winds, local surges in water levels have impacted coastal communities.  The National Weather Service is responsible for alerting these communities of threats to life and/or property and this includes the issuance of Lakeshore Flood Warnings.

Flooding from a localized rise in lake level can cause road closures, flood water damage to businesses and homes, cause marinas and beaches to be inaccessible (including ferry service), and produce significant property/shore erosion. While recent flooding has been focused on the western lakeshore, these impacts can also take place across any part of the lakeshore with the right meteorological and lake level conditions.

When high water is expected on the western basin of Lake Erie the National Weather Service will often use the water level at Toledo as a reference value. Minor flooding usually develops when the water level at Toledo reaches 72 inches above Low Water Datum. Flooding increases at water levels of 80 inches or more and is quite significant at water levels at or above 90 inches. The current water level for Toledo can be found by clicking here.  

The National Weather Service works closely with local emergency managers to relay impacts from the lakeshore flooding.  Impacts from the high water can also be relayed to the NWS Cleveland office via email (nwscle@noaa.gov) or through facebook.com/NWSCleveland and twitter.com/NWSCLE.