There is a reason why all the talk lately has been about Sandy. We are looking at quite the dangerous situation developing towards the end of the weekend into early next week. Historically, this storm will rival many of the past storms that have impacted New England. Not only will the track be unique, but also the intensity will be one for the record books…with minimum pressures falling to levels comparable to some of our greatest hurricanes! Just Incredible.
Gallery: Latest Sandy Forecast Maps
There is some nice weather however before Sandy approaches. Although we have widespread fog across much of central New England this morning, expect this to lift towards afternoon with everyone getting some sunshine, allowing temperatures to rise into the middle 60′s. This eerily tame weather is the calm before the storm. Clouds to our west will have a tendency to increase during the afternoon.
As we head into Sunday, Sandy will begin getting her act together. A strong upper-level trough will be swinging down from the central part of the country, and it’s energy will be fed into Sandy, allowing for explosive development. Meanwhile, upper-level ridging, also known as a blocking pattern, will force the trough and Sandy to combine forces. As this occurs, Sandy will begin losing tropical characteristic as it transitions form a warm-core storm to a hybrid “extratropical” storm. As this transition takes place, Sandy’s wind field will expand substantially, with tropical storm force winds likely several hundred miles outside of the center! These winds will slowly begin approaching the region from the southeast as we head through Sunday afternoon. Clouds will be on the increase, humidity will increase, and winds will begin gusting from the northeast, reaching 20-40mph along the coastline by day’s end.
Overnight Sunday into Monday, Sandy’s structure will continue to change as it absorbs the energy from the west, and becomes “vertically stacked” with the pressure field aloft. As this occurs, a very strong upper-level jet will develop as several short waves amplify the upper-level pressure gradient. This strong jet will enhance Sandy’s ability to breathe (enhancing upper-level divergence), and as a result she will continue to strengthen and will eventually begin to bank westward. Where and when Sandy begins this westward shift in track will dictate exactly where landfall occurs. Right now, it appears most likely landfall will be somewhere along the central/southern NJ coastline. I have increased confidence in this as almost all model guidance has landfall within 75 miles of central NJ.
With this track, Sandy will pass close enough to the New England to yield substantial, damaging effects. These effects will be quite noticeable by early Monday morning as winds increase from the northeast to 30-50mph. This is when the first rain bands will rotate through, producing locally heavy rainfall. Monday afternoon through the evening, the worst of the storm arrives. Winds will gust at or above 50mph across nearly ALL of New England as Sandy bottoms out near 950mb! Along the coastline, winds will be strongest with sustained easterly winds of 35-50mph with gusts potentially reaching 80 mph on the Cape & islands and along the south coast. Gust to 60+ inland…but that is all track dependent. Winds of this magnitude will do considerable damage, downing trees and power lines and knocking out power to thousands. Farther inland, sustained winds will be much less, in the 25-35mph range, however peak gusts may still exceed 60 mph…extending all the way up into Northern New England! Climatologically, this is very rare for New England. Historically, this is a set up for a disaster for New York City. Winds racing over 100 mph aloft will likley be strong enough to blow out windows on some of the skycrapers. Storms surge flooding will pile into the 90 degree right angle near Manhattan and Long Island. Flooding is likely in the subaways and airports. This looks like a worst case scenario for NYC with the storm bombing out just before making landfall.
In addition to these roaring winds, heavy bands of rain will continue through Monday evening with rainfall totals approaching 1-1.5 inches across the Cape and islands with 2-3+ inches likely inland. Urban and low-lying flooding will be likely, along with major coastal flooding and moderate to severe storm surge along the coastline, the worst of which will be along southeast facing coastlines where surge depths could reach 3-6 feet (6 feet being the worst case scenario). Astronomically, tides will already be running high, and high tides occurring during both midday and midnight on Monday and Tuesday will coincide with some of the strongest winds, which will compound the flooding issue along the coastline and send water onto many coastal properties. This tidal cycle is NOT track dependent and regardless of Sandy’s track will be worsened by the winds over a long duration.
Tuesday winds and rain will die down as Sandy moves well to our south and west. However, winds will still be gusty from time to time as Sandy will still have a notably deep central pressure. Clouds will hang tough with high temperatures in the upper 50′s to near 60.
Wednesday and Thursday clouds will be hard to break, with only a few chances for sunshine, mainly on Thursday. High temperatures will be right around average in the middle 50′s.
As Sandy approaches I strongly urge you to finish storm preparations by Sunday at the very latest. With nice weather today it would be a good idea to take advantage of that and make sure you have plenty of extra batteries, water, and even non-perishible food. Power outages will be numerous across the entire eastern seaboard, and for those of you in rural locations you may be without power for a week or more. With easterly winds, any of you with an easterly exposure will be at greatest risk for wind damage, and with many trees still full of leaves (Especially the Oak trees), not only will branches snap but whole trees may be uprooted. If your basement is one that typically floods during heavy rainfall, be prepared for the possibility of water in your basement.
Of course, we are still 2 full days away from the worst of the impacts. A lot can change within this timeframe, and nothing is set in stone just yet. Small shifts in the track of Sandy may shift the worst of the weather away from us or closer to us, so make sure you stay tuned as we provide constant coverage of this evolving storm and the historic precedents that will be set. Be safe!