 Tropical Cyclone Herbie was the only known tropical system to impact Western Australia during the month of May on record . The final cyclone of the 1987 – 88 Australian region cyclone season , Herbie was first identified northwest of the <unk> Islands on 17 May . The following day , the system was classified as a tropical low by the Australian Bureau of Meteorology and intensified into a Category 1 cyclone later that day . Several hours after this upgrade , the storm attained its initial peak intensity with winds of 75 km / h ( 45 mph 10 @-@ minute sustained ) . Around the same time , the Joint Typhoon Warning Center classified Herbie as Tropical Storm <unk> . 
