Memorial Day weekend traditionally marks the beginning of summertime, and summertime means heading to the beach. For those brave enough to enter the still chilly waters of Lake Michigan it also signals the beginning of the lake wading and swimming season.
Your National Weather Service Forecast Office in Chicago/Romeoville will be issuing a Surf Zone Forecast, or Beach Forecast, starting this Memorial Day weekend, and continuing through the end of September.
The Surf Zone Forecast will consist of information on sky condition, precipitation, temperatures, winds, waves, and an assesment of the rip current threat for Lake Michigan beaches of Lake IL, Cook, Lake IN, and Porter Counties. This includes the beaches of Illinois State Beach Park, the City of Chicago Park District, and the Indian Dunes National Lakeshore.
Rip Currents are channeled currents of water flowing away from shore. Under certain wind and wave conditions these currents can be numerous and strong. The northwest Indiana and southwest lower Michigan shorelines are prone to rip currents, especially on days when there are large waves or when strong, fast moving, gusty thunderstorms move in off the lake, continuing for a period even after skies clear as minor seiches can be generated that can add to rip current development.. In addition, winds blowing parallel to the shoreline can lead to localized strong rip currents near piers, break walls and other structure that extend out into the lake.
People planning to go Lake Michigan beaches to swim or wade this summer should check the Rip Current Outlook in the Surf Zone Forecast and always obey lifeguards, park rangers, posted signs and warning flags regarding the potential danger of entering Lake Michigan waters. Many drownings due to rip currents have been the result of the victims ignoring these warnings and beach closing notices.
When the potential of rip currents is elevated to the moderate or high catagory, this information wil also be included in the Hazardous Weather Outlook as well as the Lakeshore Hazard Message products issued by the Chicago/Romeoville NWS office. For those heading to the southwest lower Michigan shores Rip Current information and beach conditions are available from the NWS Northern Indiana and NWS Grand Rapids offices.
Rip Current Outlook in NWS products will use the following 3-tiered text qualifiers…
Low Risk… Wind and/or wave conditions are not expected to support the development of Rip Currents. However, Rip Currents can sometimes occur, especially in the vicinity of jetties, break walls, and piers. Know how to swim and heed the advice of Lifeguards.
Moderate Risk… Wind and/or Wave conditions support stronger or more frequent Rip Currents. Only experienced swimmers should enter the water.
High Risk… Wave conditions support dangerous Rip Currents. Rip Currents are life-threatening to anyone entering the water.
The Surf Zone/Beach Forecast for the Illinois and Indiana lakeshore can be found here... www.crh.noaa.gov/product.php (from the main NWS Chicago/Romeoville menu bar, under the Forecasts section, click on Local Area, then under Latest Forecasts for Northern Illinois and Northwest Indiana section click Lake Michigan Beach Forecast for Illinois and Indiana.
Specifics on the product identifiers for the new Surf Zone Forecasts in the Great Lakes can be found here... www.weather.gov/os/notification/scn09-17surf_great_lakes-1.txt
For more information on rip currents, visit NOAA’s Rip Current Safety web page at www.ripcurrents.noaa.gov and the National Park Service Indiana Dunes National Lakeshore Rip Current information web page at www.nps.gov/archive/indu/rip.htm.
Have a fun and safe day at the beach.