Siren test April 11. #OceanaCountyEmergencyManagement HART — Oceana County Emergency Management, in cooperation with Mason/Oceana 911 and local fire departments, will conduct a test of the county warning sirens Wednesday, April 11, at 1 p.m. April 8–14 is National Weather Service Severe Weather Awareness Week, and on April 11 National Weather Service offices in Michigan are conducting a statewide simulated…