Where a coastal storm will bring high winds, waves and coastal flooding this weekend
A strengthening storm system is set to sweep up the East Coast this weekend, bringing days of expected rain, wind, rough surf and beach erosion along hundreds of miles from Florida to Long Island and southern New England. While the system won’t meet the technical requirements to be classified as a named storm, it will bring tropical stormlike impacts and could damage more homes in the recently battered Outer Banks.
It remains unclear whether the storm will from there nudge back westward, bringing nasty weather closer to Interstate 95. For now, it looks like the worst weather will target coastal areas, though major cities - like New York, Newark, Philadelphia, Baltimore and Washington D.C. - will still be plenty stormy.
“Numerous roads may be closed,” wrote the National Weather Service in Jacksonville. “Low lying property including homes, businesses, and some critical infrastructure may be inundated. Some shoreline erosion may occur.”
On the Outer Banks, meteorologists are considering issuing a coastal flood warning, signifying a more serious coastal flood threat. Between Sept. 30 and Oct. 1, rough surf caused eight abandoned homes on the Outer Banks to collapse into the ocean, and more structures could be threatened this weekend.
There could also be cascading flight delays due to strong winds affecting runways, an unwelcome disruption at a time when air travel is already adversely affected by the government shutdown.
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Conditions and timing of the storm
The storm will first materialize between Florida and the Bahamas late Friday night as a weak wave of low pressure. It will be energized by an approaching upper-level trough, or jet stream dip filled with cold air, low pressure and spin aloft.
That synergetic overlap of both systems will allow the storm to strengthen as it works northward paralleling the East Coast. By Friday night, onshore flow will begin to batter the Carolinas, coastal Georgia and northeast Florida, with gusts of 30 to 40 mph. Those winds will pile water against the coast, leading to a couple feet of storm surge. That will combine with large breaking waves of 5 to 7 feet to cause pockets of coastal flooding.
By Saturday night, the system will lift northward, spreading gusts of 45 to 55 mph to the coastlines of the Delmarva Peninsula, New Jersey and Long Island. A few gusts up to 65 mph are possible just offshore of New York City. Cape Cod and the Islands could see gusts over 55 mph as well.
It’s a bit early in the season for a “nor’easter” to impact southern New England. While the region is accustomed to autumn storm systems, the presence of fully-leafed trees could result in more power outages as the winds pick up.
The storm will also be pinwheeling moisture ashore, leading to heavy rain. A general 2 to 4 inches is expected within 50 miles of the coastline from North Carolina to New York, but amounts will drop off quickly westward.
Forecasted rainfall in Washington D.C., for example, will walk a tightrope - several inches are likely east of the nation’s capital, but to the west, sinking air on the periphery of the storm system may limit rainfall totals to barely a half inch. Boston’s forecast is equally tricky - several inches are possible on the Outer Cape, but Boston proper may see much less rain.
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Why won’t this storm have a name?
There were initially some discussions that this system could acquire some tropical or subtropical characteristics. That’s still probable, but it’s unlikely the storm will get a name. That’s because the bulk of the storm’s energy will come from the jet stream, or a river of winds in the upper atmosphere. Tropical systems harvest energy from warm ocean waters. While this particular coastal storm will tap into some ocean heat energy on Saturday, it won’t be enough to markedly change the storm’s overall structure.
Instead, the low pressure system will probably become a warm seclusion - that means a bubble of warm air will pinch off near the storm’s center, but the overall storm will still be anchored to fronts and the jet stream, keeping it nontropical.