Gordon the latest storm on a well-worn path to Canada
Meteorologist
Wednesday, September 5, 2018, 10:37 AM - Small but potent tropical storm Gordon crashed onshore over the central Gulf Coast late Tuesday, with reports of at least one fatality in northwestern Florida. Gordon's extended track now takes it on a curving course toward Canada, but Gordon won't survive long enough to bring significant impacts to Canada and it's not because of the track -- other storms on a similar path have made their mark on our history books.
We take a look at what we can expect from Gordon, and how the storm compares to its predecessors, below.
(See also: Florence trails Gordon as Atlantic hurricane season peaks)
TRACKING GORDON -- FROM THE GULF TO THE GREAT LAKES
Gordon made landfall late Tuesday west of the Mississippi-Alabama border as a tropical storm, failing to attain hurricane status. As of Wednesday, Gordon has diminished into a tropical depression over the southern U.S.
Ahead, Gordon faces a long trek up through the central United States, away from the warm, inviting waters of the Gulf of Mexico. The lack of heat and moisture, combined with increased drag from moving over land will further weaken Gordon into a post-tropical low later this week.
It won't be until later, after it gets scooped up by a low pressure system carving its way across the central U.S., that we can expect any impacts from the storm -- or what's left of it -- in Canada. Long range model guidance has the remnants of the storm merging with this separate low pressure system before this new combined feature begins moving northeastward, toward the Great Lakes, on Sunday. It remains to be seen how far north this system will track, but southern Ontario will likely see at least some rain from it as it moves past the region. 'Some rain' isn't exactly the stuff major storm impacts are made of, but that hasn't stopped other storms from having a more profound effect.
NOT THE FIRST STORM TO PASS THIS WAY
While Gordon's impact on southern Ontario and Quebec is unlikely to be particularly impressive, it's not the first storm to make the journey from the Gulf to our part of the world, and the same can't be said about them. As the map of historical tropical storm and hurricane tracks, below, shows southern Ontario and Quebec see their fair share of leftovers when it comes to tropical activity, even though the region isn't at risk of the direct strikes we sometimes see in Atlantic Canada.
Historical tropical system tracks. Image courtesy NOAA/NHC.
The grey lines in the image represent portions of the track where the storm in question had already diminished to an extra-tropical state, with blue indicating tropical depression strength, and green -- the highest we see here for Ontario -- representing tropical storm strength systems. Note that this map shows only tracks for those storms that came within 200 nautical miles (370 km) of southern Ontario.
Some of the more significant storms to sweep into southern Ontario from the Gulf Coast were Arlene and Dennis, both products of 2005's merciless hurricane season. Another thing these two storms had in common was a stronger starting point; Dennis was a category 3 storm when it made landfall in the Florida Panhandle. Even so, the path across the entire contiguous United States is a rough one for any tropical system, and Dennis was classified as a remnant low by the time it crossed the border near Sarnia, with winds of only around 10 knots (about 18 km/h).
TAKING A SHORTCUT
It's no coincidence that the strongest and most memorable tropical systems (or their remnants) that have impacted Ontario and Quebec have been those that made landfall along the Atlantic Coast rather than in the Gulf of Mexico. While the lows have to scale the Appalachians to reach us on this track, it's still a much shorter distance to travel over land, giving storms a better shot to retain their strength, and occasionally even some of their tropical characteristics, by the time they reach the Lower Great Lakes.
Image courtesy NOAA/NHC
Image courtesy NOAA/NHC
Image courtesy NOAA/NHC
The last post-tropical system to skim past southern Ontario was 2017's Nate, which sped by south of lakes Erie and Ontario in early October. That system brought a widespread 15 to 30 mm of rain across southern Ontario.
