With a single tide, a community can have its risk altered due to a coastal storm. The following nor’easter offshore trains that old East Coast combination snow, wind, and surf pounding, but what is more important is the fact that ocean and infrastructure collide simultaneously the ocean water pushed up and at the same time the high tides raise the baseline.
It is predicted that a storm will develop off the Carolinas and then intensify quickly in the Atlantic, with the greatest danger along the Outer Banks, along the coast of Mid-Atlantic, up to southeast of New England, and Cape Cod, and the islands. The factor that compounded the situation was well outlined by the National Weather Service office that serves Newport/Morehead City in North Carolina, where it wrote: This potent coastal storm will also be accompanied by an enhanced cycle of tidal action that will amplify potential coastal flooding effects.
The reason why nor’easters are not as much about a single hazard as a negotiation between time and space is that overlap. Powerful winds channel water into the coastlines and waves pile up above it and the line between inconvenience flooding and property losses may narrow down to which side of a barrier island roadway is high enough. The forecast mix of huge swells and full moon tides makes what would be just another winter day in the Outer Banks into a challenge. In the offshore, the wave height can be 15-30 feet towards the end of Saturday to Sunday and the wind speed might be particularly intense along the vulnerable headlands.
The story of the storm is more jittery inland.
The Washington to New York axis is often the national euphemism of the East Coast disruption, but this arrangement is an example of why local results cannot be reverse-engineered with one map. A slight shift in the storm track may cause the band of heavy snow to pass off-shore, or be pulled onshore, turning a weekend of slushy sidewalks into dry pavement. Such uncertainty is more a failure of prediction than the characteristics of the coastal storms: the precipitation, wind and coastal effects have tight gradients due to sharp temperature contrasts and rapidly intensifying lows.
Cold air that pushes south with its direction begins at the start and the warm ocean air opposes it. That line, known by meteorologists as a baroclinic zone, serves as an intensification runway particularly when a storm is over hot Atlantic water. Below a sufficiently rapid pressure drop, the storm is classified as an explosive cyclogenesis, which is the mechanism of bomb cyclone headlines. The term is operatic, yet the practical implication should not be ignored: quick intensity may only increase the steepness of the winds, the magnitude of the waves, and entrap heavy precipitation before road workers and local residents can respond.
To the New England, the amount of snowfall will depend on the minute variations of ocean-side warmth and the location where the core of the storm systems have become established. One forecast of the National Weather Service put Hyannis at about 10 inches, with other models ranging higher and lower. What the reader is concerned about is not the actual number, but what those inches translate to when combined with puffing winds: poor visibility, straying and the sort of transportation that decays fast when the weather turns colder.
The cool air moves far south of the storm pushing into the Gulf Coast and Florida. The Sunday low in Miami was estimated to be about 36 degrees, just like the day would have been the lowest recorded in Miami history. That chill, in South Florida, where 30s are considered a rarity, will make a story about a coastal storm seem a home one, changing pipes, pets, outside plants, school mornings, all that with weather that seems to have no natural place.
Even that cool frosty shock is in a broader climate contradiction. Most of the planet has been warmer than average since the beginning of winter with a few exceptions, such as parts of the central and eastern United States, being the colder than usual with the aid of disturbances in the polar vortex. The nor’easter, as it were, does not disapprove of warming as much as it is a warning that at some time or other local extremities show up on time, and that, in the case of coastline, the water level at the time when the wind starts to howl is the most important variable of all.
