National Weather Service United States Department of Commerce

Effective Wednesday, September 19th, 2018, the preparation of the Open Lake Forecast for Lake Michigan will transfer from Weather Forecast Office (WFO) Chicago/Romeoville to WFO Milwaukee/Sullivan.  The Open Lake Forecast for Lake Michigan will not change, only the issuing office and the WMO header. 

The current identification header for the Open Lake Forecast for Lake Michigan is CHIGLFLM and WMO header FZUS63 KLOT.   The new identification header for the Open Lake Forecast for Lake Michigan will be MKEGLFLM and WMO header FZUS63 KMKX.  

Along with this change, long-fuse marine watches, warnings and advisories for the Lake Michigan Open Waters will transfer from WFO Chicago/Romeoville to WFO Milwaukee/Sullivan.  

Also, the Hazardous Weather Outlook for the open waters zones on Lake Michigan will transfer to WFO Milwaukee/Sullivan.  No new products will be created with these changes, but users will need to monitor the Marine Weather Warning and Hazardous Weather Outlook products from WFO Milwaukee/Sullivan to continue receiving forecast information for the Lake Michigan open waters.  

open waters map

The official National Weather Service change notice is located here.