On Wednesday, 4 October 2017 14:20:22 UTC+1, N_Cook wrote:

From what I remember of the storm, there was no awareness by anyone
,prior to the 87 storm, about its upcoming severity, during the day before.

This was partly a "failing" in the understanding of the meteorology. The enormous, threatening "cloud head" was there and today's meteorologists would view this with a fair amount of horror as it would have signalled the potential for rapid cyclogenesis.

However - if you take a look at the pressure drops in the centre of the storm, it's absolutely nothing remarkable compared to other storms. I did a bit of work for an old company who had digitised all the Atlantic pressure maps going back to 1900 and the 87 storm was maybe about the 50th or 60th most rapid deepener.

The slow, steady development of the storm I think is responsible for the long-lived nature of the sting jet that helped cause such notable damage. When storms rapidly deepen they wrap up quickly and any sting jet signature is fairly quickly overrun by the cold conveyor belt, the traditional source of the strongest winds. This is purely a hypothesis mind...

Richard