Last Saturday, in the Northern Atlantic to the south of Iceland, the extratropical storm Jolle, intensified dramatically. Meteorologists use central pressure as a proxy for measuring the strength of a given storm. The lower the barometric pressure, the more intense the storm. By this standard, Jolle, whose central pressure dropped to slightly below 930 mb, was more intense than Superstorm Sandy, which dropped to a pressure of 940 mb. Fortunately, the storm Jolle did not strike land. The old expression to describe storms as moving “safely out to sea,” has never set very well with mariners, but one hopes that in these days of weather routing that most ships avoided Jolle.
The all time record for lowest barometric pressure for a North Atlantic extratropical storm is 913 mb, set on January 11, 1993. During that storm, the 90,000 dwt tanker Braer was caught out in the storm. Piping on deck broke allowing saltwater to enter the fuel tanks, disabling the engine and causing the ship to drift onto Garths Ness on the Shetland Islands, resulting in a significant oil spill.