A flood advisory was issued by the National Weather Service on Thursday at 4:08 p.m. EST in effect until Friday at 7 p.m. EST for Newaygo County. A flash flood warning is issued when a flash flood is either imminent or already occurring. Flood warning: Take action! A flood warning is declared when flooding is on the verge of happening or is already underway. Flood advisory: Be aware:A flood advisory is issued when flooding is not expected to be bad enough to issue a warning.