AccuWeather.com

By Kristina Pydynowski, Senior Meteorologist

Aug 27, 2011; 10:55 PM ET

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This photo shows a sail boat in trouble along the lower Chesapeake Bay. Photo by AccuWeather.com Facebook fan Gaye S-C.

"The notion of a storm surge to 11 feet in New York City is unfounded."

Coastal flooding from Hurricane Irene will not only tear up beaches that line the Atlantic from the Carolinas to New England, but also will also submerge some shores along neighboring bays and sounds.

As Irene moves northward right along the East Coast, its strong winds will drive the ocean on shore (a phenomena called a storm surge) and raise water levels from northern South Carolina to the southern shores of New England.

According to Expert Senior Meteorologist Alex Sosnowski, "The notion of a storm surge to 11 feet in New York City is unfounded."

The storm is too weak and moving at the wrong angle says Sosnowski.

"This is not a Category 3 or 4 hurricane moving in from the southeast at northern New Jersey, but rather a Category 1 storm that will be weakening moving northward," Sosnowski added.

There will be problems, but this is not the Armageddon storm in terms of storm surge people are making this out to be for New York City. Minor flooding of Battery Park is likely, but has occurred in the past.

The storm surge will raise water levels about 3 feet above published values on average, with parts of the Outer Banks of North Carolina and Long Island enduring a 3- to 6-foot surge.

These are the published high tides that are likely to cause the most problems, when coinciding with Irene.

Adding to the situation will be pounding waves on top of the water levels.

Making the situation worse, is the arrival of the storm with the new moon and the astronomically high tide levels associated with it. However, Sosnowski cautions, the astronomical tides are figured into the normal, published levels (high and low). These published values are calculated years in advance. There has been a tendency to misread projected storm influence water levels as a result.

It is not just the beaches that line the Atlantic Ocean that are bracing for coastal flooding, but also neighboring bays and sounds.

AccuWeather.com meteorologists expect that these smaller inlets will experience the greatest rise in water.

North Carolina Inlets

Irene's hurricane-force winds continued to drive water into the western branches of Albemarle and Pamlico sounds

The AccuWeather.com Hurricane Center is especially concerned for significant coastal flooding in the section of the Pamlico Sound that connects to the Neuse River, leading to flooding upriver in New Bern.

As Irene departs the Outer Banks Saturday evening, coastal flooding will remain a threat, as winds across eastern North Carolina take on a westerly component and push the water to the western shores of the Outer Banks.

Chesapeake Bay

The lower Chesapeake Bay is experiencing a rise in water, which will continue into Saturday night.

A water-level rise of a foot or so is expected over the northernmost parts of the Chesapeake Bay including the Baltimore Inner Harbor.

The worst coastal flooding is expected along the waterfront of Norfolk and Newport News as northeasterly winds drive water into the mouth of the James River.

Since Irene will not press inland into central Virginia, a significant amount of water will not get pulled farther north into the upper Chesapeake Bay. Tides will run about 1 foot above published values at the Baltimore Inner Harbor.

Delaware Bay

Saturday night, the danger of coastal flooding will shift northward to the Delaware Bay.

The water could back up into the lower Delaware River and create minor flooding issues along the waterfronts of Wilmington, Del., and Philadelphia.

New York City Area

Coastal flooding issues will reach the New York City area Saturday night into Sunday morning prior to Irene slamming onshore during the day.

Northeasterly winds circulating around Irene will drive water from Long Island Sound into the East River, potentially raising water levels to 3 feet above published levels along the shores of the Bronx, Queens and the east side of Manhattan.

While these river levels would not inundate the entire city, Battery Park may experience some flooding as it has in the past on multiple occasions.

A similar or slightly higher rise in water levels is expected as the winds push water from the Atlantic Ocean into Raritan Bay, leading to coastal flooding issues along the eastern and southern shores of Staten Island and neighboring New Jersey.

Water could also back up the Hackensack River, flooding locations along its banks.

New England

Weighing in the large size of Irene and the fact that it will weaken to tropical storm status while approaching, in general, water levels of 1 to 2 feet above published values are to be expected.

Around Narragansett Bay, where the worst conditions are expected along the southern coast of New England, water levels around 2 feet above published values are forecast.

"While coastal flooding will be serious, but not extreme, power outages and flash flooding are an entirely different matter," Sosnowski added.