From first person experience ( I was surfing in Southern Bass strait waters ) , it was a cut off that formed west of the Strait and Barreled through it in a day and intensifying as it went . Started out quite a smallish low and by the time it reached the Fleet a day or two later on the Far Sth Coast of NSW it smashed em up . The Leaders experienced Swells of " Incredible Magnitude " , all i remember is that the wind was strong but the Swell Grew really quick and had quite a short period . ie it was the local storm that produced it .
I'm sure others could shed more light " Meteorologically?? ". All i know at this very early stage , this Model seems to show a weather bomb of sorts .
Broad area of Low pressure associated with a Trough , advancing Cold Front . And then BAM .
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Quote " If you want to save our world, you must hurry. We don't know how much longer we can withstand the nothing. "