October 27, 2012
An extremely rare and dangerous storm will turn in from the Atlantic, putting 60 million people in its path and could lead to billions of dollars in damage.
Hurricane Sandy is expected to slam into central or southern New Jersey Monday evening, but severe and catastrophic impacts will threaten the mid-Atlantic and southern New England much sooner.
Conditions will deteriorate Sunday into Sunday night with the worst of the storm raging Monday into Monday night. Rain and gusty winds will even expand westward to the eastern Great Lakes and upper Ohio Valley Monday into Monday night.
Sandy will weak over land on Tuesday, but conditions will remain adverse throughout the Northeast, eastern Great Lakes and upper Ohio Valley.
Ripple-effect flight delays and cancellations are possible over a large part of the nation starting Monday, as the storm will target major airports from Boston to Washington, D.C., with New York and Philadelphia in the middle. Many aircraft originate from or travel to these hubs on a daily basis.
Impacts from heavy rain and wind will be felt hundreds of miles inland and the power in some neighborhoods could be out for days.
Storm surge flooding will occur over a much larger area, when compared to a hurricane and more severe than a typical nor’easter. It is likely to be more than just a few waves over washing the seawall in the hardest-hit areas.
Sandy has the potential to bring historic storm surge flooding near and north of the center.
It is possible areas from New Jersey to New York City and Long Island have some of their worst coastal flooding on record with Sandy tracking into New Jersey.
The same can be said for the Delmarva and Philadelphia areas if Sandy makes landfall farther south around the Delaware Bay and the Delmarva, a solution AccuWeather.com meteorologists are closely monitoring.
Communities, neighborhoods, roads, rail yards, subway stations and other low-lying areas near the coast, generally north of the track can take on feet of salt water.
AccuWeather.com meteorologists are expecting a storm surge of 5 to 10 feet, but locally higher levels are possible near and just north of the storm track.
The full moon during the afternoon of Monday, Oct 29. will add to high tide levels spanning the 28th through the 30th.
Near-coast waves will average 10 to 15 feet, while seas well offshore will range from 30 to 40 feet.
Damaging wind gusts will reach from Boston to Washington, D.C., and inland to the central Appalachians. Sandy will not be your typical hurricane when it moves in from the southeast. Hurricanes are small and compact.
Sandy will be more like a large nor’easter on steroids. It could have the strength of a Category 1 or 2 hurricane. Tropical storm and hurricane-force wind gusts will extend out hundreds of miles from the center, so focusing on the center alone in terms of the severity for wind and rain is not recommended.
There is the potential for tens of thousands of trees to be downed and millions of utility customers could be without power at some point. Flying debris, including airborne panes of glass in the larger cities will pose a danger. Some secondary roads could be blocked by trees. Depending on the landscape, such as heavily wooded areas, the power could be out for a week or more.
Flash, urban and small steam flooding from rainfall will also be a significant impact. Sandy has the potential to bring a half of a foot of rain to some areas on its west, northwest and north flanks.
Places in Delaware, southern New Jersey and southeastern Pennsylvania–including Philadelphia–should top Sandy’s rainfall totals with more than 8 inches expected.
Fallen leaves will block storm drains in some towns and cities. Small streams will immediately rise in response to the rainfall.
Enough cold air will wrap into Sandy’s far western side to bring heavy, wet snow to the mountains from northern North Carolina to southwestern Pennsylvania Monday into Wednesday. It is possible that snow zone extends northward to extreme western New York.
Snowfall should top a foot in the higher terrain of West Virginia.
Not So Historic
Only the preexisting dry state of the ground and low river levels should spare most areas from major river flooding. However, many rivers will have significant rises into the middle of next week.
Central and northern New England will be spared the worst of the storm due to the forecast track well to the south. However, there will be problems with strong wind gusts, heavy rain, coastal flooding and beach erosion. These conditions will trend more serious heading west along the South coast.
Eastern North Carolina will be spared the worst as well with the storm making landfall to the north. However, north to northeast winds will bring above-normal tides and coastal flooding concerns to the Outer Banks. Strong, gusty winds can also cause power outages during and in the wake of the storm for a time.