Sandy will be an historic storm – as of Sunday evening, this is a virtual guarantee as all forecast models are in strong agreement, predicting the worst case scenario of a landfall just south of New York City late Monday.
This storm deserves the hype, but it is very important to separate the US impacts from the Canadian impacts.
Southern Ontario is going to take the hardest hit from Sandy. There will be wind and rain in Quebec and the Maritimes, and even snow in Northeast Ontario, but the worst conditions are likely in Southern Ontario. However, this is unlikely to be an epic storm for us – rather, Sandy’s impact will be on par with a strong fall storm, the type we see every few years. Strong winds from Sandy will lead to some scattered power outages. It will be very windy later Monday into Tuesday morning - guaranteed - the only question is how strong the gusts will be.
Peak gusts for most places should remain below 100 km/h – still strong enough for some trees to come down and some power outages, but not heavy damage.
The exception to this will be along the southern shores of the Great Lakes. In fact, Sarnia may end up seeing some of the strongest winds of anyone Monday night – not what you’d think considering Lake Huron will be farther from the centre of the storm than Lake Ontario.
This storm will behave more like a large fall storm than a hurricane once it has moved inland, and the northerly wind blowing down the length of Lake Huron coupled with colder air on the backside of the storm means that areas around Sarnia may see wind gusts in excess of 100 km/h.
This could be enough to cause significant shoreline erosion and potentially infrastructure damage.
Motorists in Southern Ontario should keep in mind that a strong grip on the wheel will be needed on the Burlington Skyway and Garden City Skyway, especially Monday night.
Recent rainfall has saturated the ground in Southern Ontario, and with heavier rain developing later Monday as Sandy’s moisture moves in, some flooding is possible. However, this is not expected to be a Hurricane Hazel type historic rainfall.
Some power outages are likely on our side of the border, but we need to clarify that the greatest impact will be in the US Northeast and Mid-Atlantic, where it is likely that millions of people will lose power.
As bad as this sounds, the most concerning aspect of this storm isn't the wind or the rain, but the storm surge potential for Long Island Sound and areas around New York.
Sandy is taking the perfect track, and its slightly faster timing for landfall means that the highest storm surge is likely to correspond with high tide Monday evening.
Predicting the specifics of a storm surge is a tricky business because it involves not just the dynamics of the atmosphere, but also those of the ocean. However, it seems clear that all-time high water marks will be threatened by Sandy’s surge, which could lead to massive infrastructure damage in low-lying areas of Connecticut, New York and New Jersey.
Is the Hype Deserved?
Yes – while Sandy will not produce the horrific scenes of a Katrina or Andrew, it will take a serious human and economic toll on the U.S. because of its size and location of impact.
While this will not be an epic storm for Canada, it is still a strong storm that will make for an uneasy sleep for many on Monday night.
For live updates and analysis tune to The Weather Network on TV and track Sandy’s progress here on the web.