How far north in the Atlantic Ocean do storms become or remain effective as hurricanes or (something other than tropical) storms? Are these storms potentially hazardous to ships at sea and land masses such as Greenland and Iceland, or Canadian and Scandinavian coastlines?
Posted July 28, 2008
MIKE MOSS SAYS: Patricia, Tropical cyclones often track as far north as 50-60 degrees latitude (see the global track map at right), occasionally with continued tropical characteristics, often as hybrids undergoing transition to an extratropical character, and often as extratropical remnant lows, some of which still retain heavy precipitation and very strong winds. One storm, Hurricane Faith of 1966, reached a latitude of around 65 degrees north as a category two hurricane, passing the Faroe Islands about halfway between Iceland and Norway before being reclassified as extratropical. The storm then crossed into Scandinavia and the eventually drifted to within 300 miles of the north pole before dissipating.
You can see that track and a few others that have moved into that general area on the enlarged section of the global tack map covering the area near Europe (second image). A similar zoomed image shows tracks that have affected the Canadian maritimes and even up to the west of Greenland in a couple of cases. Nova Scotia and Labrador in particular have been hit by quite a few storms, a small number of which were still classified as hurricanes.
So the answer to your last question is yes, these low pressure systems can still be quite hazardous at sea or upon making landfall, regardless of whether they retain the designation as a hurricane or tropical storms, or have become (as the Canadian Hurricane center calls them) "post-tropical" storms.