Friday, October 26, 2012

Major Impacts Expected From Sandy from Mid-Atlantic thru New England...

I am growing increasingly concerned about the prospects for major damage and disruption of key basic services across a large area from the Mid-Atlantic into New England, including the major city beltway from Norfolk through Baltimore/Washington, Jersey City, Atlantic City, Philadelphia, New York City, Providence and Boston.

At this time I feel that too many are focused solely on where the center of Sandy will make landfall.  While I don't want to say that is irrelevant (because it's not, especially when looking at storm surge), I want to emphasize that the wind field associated with Sandy is very large and will grow larger before impact early next week.  This means that locations far removed from the center will experience extended periods of tropical storm and/or hurricane force winds.

More on the potential impacts in a minute.  For now...let's take a look at the latest particulars...

As of 4pm CDT / 5 PM EDT, the center of the system was located about 60 miles North of the Great Abaco Island, or about 420 miles South/Southeast of Charleston, SC:



Maximum sustained winds are estimated at 75 mph, and the minimum central pressure is 28.67 inches of mercury (971 millibars).  

Sandy is moving toward the North at 7 mph, and this general motion is forecast to continue into tonight, with a gradual curve toward the North/Northeast and then Northeast during the day Saturday.

The track through Monday is pretty straight forward, and I generally agree with the latest National Hurricane Center (NHC) forecast as shown below through 2pm Monday:


As you've probably noted, Tropical Storm Warnings have been issued for portions of the Florida and Carolina Coasts, based on the already large and ever expanding wind field associated with Sandy.  Even though the center will remain hundreds of miles to the East of these areas, sustained winds of tropical storm force can still be expected.  The time frame involved for this portion of the impacts is tonight through mid-afternoon Saturday for the Florida coast, and Saturday night through Monday for the Carolinas.

It is from Monday afternoon through Tuesday morning where some uncertainty remains with respect to the exact track of Sandy.  Model consensus is sharpening, but there still remains a spread from the mouth of the Chesapeake Bay through the Boston area, as you can see on the latest composite model track image below: 


As you can see, the bulk of the models are focusing on an area from the mouth of the Delaware Bay (just South of Philadelphia) through New Jersey as the most likely point of impact.  In general I agree with that assessment at this time, insofar as where the center of Sandy is most likely to make landfall early on Tuesday morning.

I believe the latest runs of the European (ECMWF) and U.S. based GFS models show the  "extremes" of the most likely landfall points.  The ECMWF continues to favor the southern Jersey shore, image below valid 8am EDT on Tuesday:


...while the GFS continues to shift to the Southwest, with the latest run depicting a landfall just off the Eastern end of Long Island (image also valid 8am EDT on Tuesday):


As I mentioned above, I believe the actual impact of the center will lie between these two model depictions, with the Jersey Shore just South of NYC looking particularly vulnerable.

Regardless of exactly where the center of Sandy makes impact early Tuesday, a major blow will be dealt to the entire region.  Power outages will be widespread and tree, powerline and structural damage from extended periods of tropical storm and hurricane force winds will cause billions of dollars in damage.

If landfall takes place right in between the current ECMWF and GFS solutions, it would be a "worst case scenario" for the New York City Metro area.  A potentially devastating storm surge would be pushed up the Sound and into the Hudson and East Rivers, while torrential rain falls over the city and tries to force its way back Southward on the same bodies of water - causing widespread additional flooding.  The windows of the middle and upper floors of sky scrapers would be blown out on a widespread basis under such a scenario, not to mention the wind damage that would be taking place down at the surface.

With the above in mind, I highly suggest that folks in this region take this situation very seriously.  Make preparations now before supplies run short, and make arrangements to stay with family or friends further to the West out of harms way if at all possible.

I read a disturbing news account of a press conference earlier this afternoon where NYC Mayor Michael Bloomberg suggested that New Yorkers plan on "business as usual for Monday", going to work and school, etc., as normal.  I think this is a very foolish suggestion to make based upon all available information at this time.  If the forecast track changes significantly over the weekend, I'll be the first to point out that it looks better, but for now, I think everyone should operate along the lines of what appears most likely - and a major hit to the NYC Metro area certainly falls under that umbrella.

Assuming a landfall of the center somewhere along the Jersey coast, which is the most likely scenario at this time, the following general impacts can be expected across the region.  First, with respect to winds:


...which will result in widespread, possibly long duration power outages for millions of people:


...and widespread, heavy rainfall will lead to widespread flooding:


Storm surge flooding will be another matter, and is likely along the coastal areas within the yellow and especially the red shaded area on the above image, in addition to the fresh water flooding threat.  We will be able to better define the most likely impacts of storm surge flooding over the weekend.

Many folks will have never witnessed a storm like this in their lifetime, and many others will never witness such a storm again in theirs.  I am not saying that to "hype" the situation, but to try and drive home the importance that everyone within the path of Sandy pay close attention to the weather and prepare now to make sure that their families, friends, homes and businesses are ready for this dangerous storm.

We live in an "always on" society.  Cellphones and laptop/portable computers are often our lifelines these days.  Among the other items that I highly suggest having in your severe weather / disaster preparedness kit, some type of cellphone battery charger and/or laptop charger should be included.  I highly recommend the Enercell Portable Power Bank.  You can charge your cellphone, tablet PC and many other USB compatible items with this device.  It is available at Radio Shack and other major retailers.

An AC power inverter is also another handy tool, like this one available at Radio Shack, Wal-Mart, Target, and other retailers.  You can plug the device into the cigarette lighter of your vehicle and provide power to any device that you would normally plug into an AC outlet.

As mentioned above, the potential exists for power outages over a large area and for a long period of time (likely for weeks in some areas).  Please make sure to stock up on non-perishable foods and get a hand operated can opener if you live in the power outage threat areas outlined above.  Wal-Mart and the Dollar Store still carry manual can openers, usually for $5 or less.  If you have a gas grill, stock up on an extra propane tank or two so that you can boil water and heat up cans of soup on the grill if need be.

This situation is serious.  I've attempted to outline the most likely threats and major threat areas as they appear at this time in the above post.  I will continue to closely monitor this situation and issue additional updates throughout the weekend.

As you might imagine, we are seeing lots of new visitor traffic here on the blog with the approach of Sandy.  Welcome visitors!  Please don't bookmark any particular post for updates, as new posts will be made each time we have new information to pass along.  Please check the homepage of the blog and refresh there for the latest posts...

If you would like to monitor the latest satellite and radar imagery associated with Sandy, please visit the Tropical Page at our sister site, WeatherGuidance.com.  We will be adding additional imagery and information throughout the coming days.

For more information from 'The Original Weather Blog', including shorter, more frequent posts during rapidly changing weather events, please be sure to follow Rob on facebook and twitter:
 

If you are in need of customized, site specific weather forecasts or storm warnings for your company or event, be sure visit Rob's professional webpage at WeatherGuidance.com.

1 comment:

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