I don't think massive is a good word for it. The supporting systems around it are not of the usual size for a storm of this intensity. It's easy to miss it on the wind map but then, all of a sudden, there are 75kt winds right around Acapulco.
I have not seen that site before. The flashes are lighting, I take it?
Nifty.
Their wind and storm predictions are really accurate, I use them every time I go on a mountain hike. I think windguru is still a bit better for sailing.