A Nor'easter Will Target The East Coast This Weekend With Coastal Flooding, Heavy Rain, Winds

What To Expect From Weekend Nor’easter

A nor'easter is forecast to develop off the East Coast this weekend, with strong winds, heavy rain and coastal flooding possible from the Carolinas to the Northeast Seaboard

It may only be the first half of October, but it's not too early for strong East Coast storms. Here's what the forecast holds.

Through Friday: Before The Nor'easter

Over the next day or so, we expect high pressure to build into the Northeast, providing nice, albeit chilly, weather there.

But along the Southeast Coast, including Florida, onshore winds will lead to areas of high surf, rip currents and coastal flooding at high tide, particularly from the Carolinas to eastern Florida even before the coastal storm forms.

This coastal flooding could reach moderate levels in a few places, including Charleston, South Carolina.

There will also be showers with locally heavy rain along the Atlantic coast in Florida Thursday, spreading to parts of the Carolinas Friday.

Then, The Nor'easter

We then expect low pressure to gradually strengthen just off the East Coast this weekend and move northward just off the coast.

This appears to fit the definition of a nor'easter, an East Coast storm in which the winds ahead of — to the north of — the low-pressure center are northeasterly.

And this storm could have some staying power. It's likely to last through at least Monday, if not lingering into Tuesday before either weakening or pulling away farther offshore.

So this could be a long-lasting slog for the East Coast, particularly from the Carolinas to southern New England.

(MORE: What Is a Nor'easter?)

Potential Impacts

High Surf, Coastal Flooding

As alluded to earlier, several days of onshore winds pushing water toward the coast will lead to coastal flooding at high tide for several days, spreading from the Carolinas, Georgia and Florida to the mid-Atlantic and New England.

In some areas, this coastal flooding could reach moderate levels, impacting streets and roads.

This repeated coastal flooding over days could lead to beach erosion, in some areas, particularly in North Carolina's Outer Banks, where nine homes have already collapsed into the ocean this year.

Winds

Stronger winds are expected to develop along the coast from the Outer Banks of North Carolina to Long Island and southern New England Sunday, and could continue along parts of the Northeast Seaboard into Monday.

These wind gusts could be capable of some tree damage and power outages in spots.

Rain

The rainfall forecast is tricky and depends on the exact track of the center of low pressure.

The closer it is to the coast, the more the heavy rain threat may be pushed somewhat inland. If it's a bit farther offshore, the heavy rain may only scrape some coastal areas.

Our current rainfall forecast is shown in the map below. For now, we expect the threat of heaviest rain to be from the eastern Carolinas to southern New Jersey.

A Subtropical Storm?

Names from the National Hurricane Center are given to tropical storms and hurricanes. This upcoming nor'easter will not be tropical in origin.

It will have more in common with low pressure systems over the mainland U.S. than a tropical storm. This is because the nor'easter will develop along a stationary front, rather than from tropical thunderstorms.

But, sometimes a non-tropical low can develop tropical characteristics. Because this coastal storm will first develop over the warm water, the low pressure circulation could warm up a bit, especially if it lingers off the Southeast coast over the Gulf Stream.

In this way it could become what's called a subtropical storm, a mix of both a tropical and non-tropical system.

The reason this matters is the NHC also names subtropical depressions and storms, issuing forecast cones, watches and warnings, as they would with a tropical depression or storm. And occasionally, these subtropical storms can warm enough to become tropical storms, even hurricanes.

For now, this chance of this nor'easter morphing into a subtropical storm are low. If that would happen, it would be named Karen.

Hayden Marshall is a meteorologist intern and First-Year Master's Student at the Georgia Institute of Technology. He has been following weather content over the past three years as a storm spotter and weather enthusiast. He can be found on Instagram and Linkedin.