I think it's pretty self-apparent? He's saying it occasionally happens but it's rare and the fact that it's happening now is a concerning data point. It's like

I think it's pretty self-apparent? He's saying it occasionally happens but it's rare and the fact that it's happening now is a concerning data point. It's like climate change: sure, historically you naturally get years with lots of hurricanes or really strong ones. But if you get, on average, more and more hurricanes and the hurricanes themselves are stronger? That's a trend.