Sandy remains a hurricane, slowly leaving the Bahamas

By: Angela Fritz , 9:28 PM GMT on October 26, 2012

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Reuters reports that the death toll from Sandy in the Caribbean is now up to 41 people as Hurricane Sandy continues its track toward the U.S. East Coast this afternoon, slowly leaving the Bahamas. States of Emergency have been declared in North Carolina, Virginia, Maryland, and New York. The hurricane is just barely still a Category 1 with surface winds of 75 mph and a minimum central pressure of 971 mb. Ocean buoys off the coasts of Florida and the Carolinas are recording sustained winds of around 45 mph this afternoon, with gusts steadily increasing and now up to 60 mph. Sandy's rainfall, which is limited to the north and northeast parts of the storm, is reaching eastern Florida, though most of it is staying offshore.

Satellite loops show an asymmetric Sandy, with almost all of the thunderstorm activity on its north side. The hurricane still has a very clear center of surface circulation which you can see on visible and infrared loops. Though the hurricane is leaving the influence of an upper level low pressure area over western Cuba, water vapor imagery shows a large area of dry air being pulled into the storm from the south, which is leading to the lack of thunderstorm activity and contributing to the weakening that Sandy is experiencing right now. The hurricane's tropical storm-force winds now extend 240 miles from the center, and could grow to 400 miles from the center by the time it reaches the East Coast.


Figure 1. Visible/infrared satellite image of Sandy as it leaves the Bahamas this afternoon. The mid-latitude trough, which Sandy will interact with over the next few days, is seen approaching from the northwest. The cold front associated with this trough is draped from upstate New York south to Louisiana, and appears as a line of clouds draped across the Midwest and South in this image.

Forecast For Hurricane Sandy

As a tropical cyclone approaches land, the worst storm surge is almost always where the winds are blowing from ocean to shore, where the wind pushes the water toward and onto the shore. In the case of Sandy's potential track, this region is on the north side of the center. In this morning's GFS scenario, Sandy's center passes over eastern Long Island, Connecticut, and Rhode Island. This would result in the highest surge north of New York City: Rhode Island, Massachusetts, New Hampshire, and possibly Maine. The ECMWF forecast from this morning is a bit further to the south. It's suggesting Sandy's center will meet land in New Jersey. This scenario opens up New York City, Long Island, Connecticut, Rhode Island, and southern coastal Mass. to the largest surge. In general, the places that will avoid the largest storm surge are those that are south of where the center of the storm makes landfall. The National Hurricane Center's forecast is similar to the ECMWF, but most importantly, its forecast is also to not focus on the exact point of landfall because of the size of the storm, and that widespread impact is expected.

The Mid-Atlantic and Northeast coasts should be prepared for a storm surge no matter their exact location. A large portion of the coast will feel the impact of up to 60 mph winds and heavy rain. According to the most recent H*Wind analysis from the Hurricane Research Division is that storm surge has a destructive potential of 4.8 out of 6.0, which is a slight increase from previous analyses. Wind damage potential is holding steady around 2.3 out of 6.0. NOAA's HPC is forecasting rainfall totals of 5 to 10 inches in the Mid-Atlantic and Northeast, and possibly more in coastal locations close to the core of the storm. Widespread power outages from Maine south to Virginia are likely, due to the combination of long-lived gale-force winds, leaves on trees, and rain that will moisten the soil and possibly increase the chances of falling trees. Snow in the Appalachians is also possible as the intense moisture meets the cold air being pulled south by the mid-latitude trough.


Figure 2. Departure of sea surface temperature from average for the Atlantic shows a large area of unusually warm waters up to 9°F above average off the U.S. mid-Atlantic coast.

Sandy to feed off near-record warm waters off the mid-Atlantic coast
During September 2012, ocean temperatures off the mid-Atlantic coast in the 5x10° latitude-longitude box between 35 - 40°N, 65 - 75° W were 2.3°F (1.3°C) above average, according to the UK Met Office. This is the 2nd greatest departure from average for ocean temperatures in this region since reliable ocean temperature measurements began over a century ago (all-time record: 2.0°C above average in September 1947.) These unusually warm waters have persisted into October, and will enable Sandy to pull more energy from the ocean than a typical October hurricane. The warm waters will also help increase Sandy's rains, since more water vapor will evaporate into the air from a warm ocean. I expect Sandy will dump the heaviest October rains on record over a large swath of the mid-Atlantic and New England.

Hurricane rains and climate change
Hurricanes are expected to dump 20% more rain in their cores by the year 2100, according to modeling studies (Knutson et al., 2010). This occurs since a warmer atmosphere holds more water vapor, which can then condense into heavier rains. Furthermore, the condensation process releases heat energy (latent heat), which invigorates the storm, making its updrafts stronger and creating even more rain. We may already be seeing an increase in rainfall from hurricanes due to a warmer atmosphere. A 2010 study by Kunkel et al. "Recent increases in U.S. heavy precipitation associated with tropical cyclones", found that although there is no evidence for a long-term increase in North American mainland land-falling tropical cyclones (which include both hurricanes and tropical storms), the number of heavy precipitation events, defined as 1-in-5-year events, more than doubled between 1994 - 2008, compared to the long-term average from 1895 - 2008. As I discussed in a 2011 post "Tropical Storm Lee's flood in Binghamton: was global warming the final straw?", an increase in heavy precipitation events in the 21st Century due to climate change is going to be a big problem for a flood control system designed for the 20th Century's climate.


Figure 3. Time series of the 15-yr running average (plotted at the end point of the 15-yr blocks) of the tropical cyclone Heavy Precipitation Index (red) and the associated 15-yr total of U.S. landfalling hurricanes from Atlantic HURDAT hurricane data base, from 1895 - 2008 (blue). Note the steep rise in heavy precipitation events from tropical cyclones over the past 20 years, which has not been accompanied by a corresponding increase in landfalling hurricanes. Image credit: Kunkel et al., 2010, Geophysical Research Letters.

Angela Fritz and Jeff Masters

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Bob Ryan ‏@BobRyanABC7
DC 50% chance having winds to 40 mph from #Sandy late Monday-Tuesday Likely N-NW winds Check trees branches north side house @abc7news
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1155. BDAwx
Quoting TropicalAnalystwx13:

No. Buoys are showing they literally extend over 400 miles out from the center of Sandy.

Buoys can't show continuity over the 450mile because they are so far apart. And I'm not saying that there aren't regions where this is true - if you look to the north of the center, there are nearly continuous tropical storm force winds to the North Carolina coast - 400-450miles away. However, to the northeast (where the NHC says the wind radius is 450miles), this OSCAT image although it may be easier to see here) shows that there is a slot where winds decrease below tropical storm force and increase again back up to tropical storm force in a band well removed from the center.

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Quoting LargoFl:
yep remember thurs folks here were saying prepare early..now imagine the people who are waiting to see where the storm goes before preparing..and my guess is theres millions of them right now, going on as if nothings wrong


There are. They live across the street. I waved at them earlier this morning as I was fixing the gutter on the side of the house.
they were just doing yard work.
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1153. ncstorm
Quoting LargoFl:
folks Think of it like this..just HOW big will this storm be?..tropical storm force winds will be 450 miles from its center...ok..thats not too much huh......look at it THIS way...how many miles is THIS?..I-95...........Virginia- 178 miles
Maryland- 110 miles
Delaware- 26 miles
Pennsylvania- 58 miles
New Jersey- 44 miles (see note)
New York- 29 miles
Connecticut- 118 miles
Rhode Island- 47 miles
Massachusetts- 97 miles
New Hampshire- 17 miles
From virginia to new Hamphshire..all at once


okay..so you saying if I mapquest my location to ocean pines, delaware and lets say it makes landfall around that area hypothetically..I would still be receiving tropical force winds if the bottom half of Sandy fills in??..417 miles is the distance...
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Quoting CybrTeddy:
A truly mammoth hurricane.


Looks like it organized overnight.. Shear decreased to 20-30 knots, which will not destroy Sandy.
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Quoting Doppler22:

I lost power for 2 days and a tree almost fell on my house
Did your family invest in getting rid of the tree?.
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Quoting LargoFl:
yep remember thurs folks here were saying prepare early..now imagine the people who are waiting to see where the storm goes before preparing..and my guess is theres millions of them right now, going on as if nothings wrong

Im all nice and prepared i just wanted to see if there were any left
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1149. K8eCane
Quoting CapeFearCane96:
The center almost looks like it's moving ENE.


it is according to nhc
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1148. wxmod
Quoting yonzabam:


Leaving aside the 'geoengineering' bit, which I assume is more of this secret government weather manipulation idiocy, how will pollution affect warming?


There are published studies that indicate geoengineering will reduce global precipitation because it will make the stratosphere more opaque, thereby reducing the difference between temperatures on the ground and upper level temperatures thereby reducing lifting air and cumulus cloud formation. You need to add "geoengineering" to your google news search. Weather modification is no conspiracy. It's standard practice.

As for pollution affecting the validity of models, black carbon soot is the main cause of ice melt in the arctic. If a model doesn't take huge and increasing global pollution into account, it is not really a useful model, is it. If you don't believe anything I say here, you need to look at MODIS satellite photos every day.

You can search the AP news for tons of info on geoengineering, weather modification, global pollution and their effects on climate. You have a computer. Just use it.

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1146. LargoFl
Quoting Doppler22:

I went to the store yesterday and i culdnt find batteries or water... I even went into Northern Maryland looking for things and i culdnt find them
yep remember thurs folks here were saying prepare early..now imagine the people who are waiting to see where the storm goes before preparing..and my guess is theres millions of them right now, going on as if nothings wrong
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Jeff Masters, meteorology director at Weather Underground, estimated there could be more than $1bn (621m) in damages from Hurricane Sandy.


This is from an article on BBC's website ^^^
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Quoting gulfbreeze:
I am not nuts and I do not drink coffe. It's just the thought of how big this Sandy will become. People do not think of this as just a cat 1 hurricane winds may be cat 1 but affect will be felt by millons of people. Just pray everyone is safe.Be ready to be with out power for days!!

I read a tweet last night, about 66million people will be effected by Sandy. DAAAMN!!!!!
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1143. guygee
Quoting BDAwx:
Remember that although tropical storm force winds extend up to 450miles away from the center, not everywhere between the storm and 450miles will have tropical storm force winds. These winds will probably be in bands far removed from the center.
You are correct, those winds are not spatially continuous but rather occurring intermittently in squalls at a distance from the storm. It is a smaller area that is getting temporal continuous high winds. For one, I know this is true because I am well inside of that circle right now.
Member Since: September 16, 2005 Posts: 0 Comments: 3167
Bryan Norcross' blog on this site (under Blogs) has a good explanation for newbies on why this storm is unusual and hard to predict. Dr. Masters is not the only expert who posts here. ;-)
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The center almost looks like it's moving ENE.
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1138. LargoFl
Quoting Doppler22:
Going through town and im seeing people taking their flags/flag poles down and putting their halloween decorations down.... Good idea people
yeah dont forget mail boxes..in a tropical storm here it blew down many, watched them travel down the street lol..funny but not funny
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Quoting washingtonian115:
Irene was kind enough to leave my power and only a few twigs and branches were snapped leaves were everywhere.Some places were without power but only 3 to the maximum in my neighborhood and since the temps were nice their weren't any complaints.

People here know its coming they just feel as though they are wasting money again.


I lost power for 2 days and a tree almost fell on my house
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Quoting Tazmanian:




are you guys nuts are some in or did not of coffe yet this AM



yes that real why would i be posting some in if it wass not real
I am not nuts and I do not drink coffe. It's just the thought of how big this Sandy will become. People do not think of this as just a cat 1 hurricane winds may be cat 1 but affect will be felt by millons of people. Just pray everyone is safe.Be ready to be with out power for days!!
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Quoting BaltOCane:


It wouldn't surprise me.

I went to the store yesterday and i culdnt find batteries or water... I even went into Northern Maryland looking for things and i culdnt find them
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Quoting CybrTeddy:
A truly mammoth hurricane.

Could give Igor a run for his money. Sandy is ridiculously big.
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Tides in Northeast Florida beginning to approach 3 feet above normal:


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A Washington Post article on Sandy's potential effect on the election...
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Quoting TomballTXPride:
The more of a perpendicular of an angle massive amounts of sea water is pushed from a storm moving toward the coast, the greater likelyhood of the most destruction surge. Couple that with the unusual high tides this month and the exceptionally shallow continental shelf especially along the Chesapeake Bay area and I'm telling you I have a very bad feeling about this.


Tomball:

If this follows the models, this is going to put so much water into Annapolis, Baltimore, and our other water communities it will cut off and probably kill some people in those areas. I have no problem with any of the hype on this storm. Just growing dread, as I watch the hours tick.
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The Mayors of Harrisburg and Philadelphia have both ordered resident sof low lying areas along the rivers to evacuate their houses and stay with relatives due to the fact of heavy flooding possible.
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Quoting Doppler22:

Irene was fairly bad for me... id like to avoid a repeat... and i really dont want to loose power
Irene was kind enough to leave my power and only a few twigs and branches were snapped leaves were everywhere.Some places were without power but only 3 to the maximum in my neighborhood and since the temps were nice their weren't any complaints.

People here know its coming they just feel as though they are wasting money again.

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Quoting Grothar:


The predicted "left hook" after 48h is interesting. This doesn't happen too often and when it does, its always a consequence of rapid deepening. When baroclinic storms rapidly deepen, they alter track to head for the lowest heights, which of course are to the left in the longwave upper trough (in the northern hemisphere). Rapid deepening is usually forced not only by jet-level divergence, but also by strong convection. All the forcing elements for rapid deepening are there; the jet, the SST's along Sandy's track, and the increasing baroclinicty of the environment after 48h.

When I was working the marine forecast desk in Environment Canada's office in Nova Scotia, I watched with fascination one night (this was in the early 90's) as an upper trof embedded in the long wave trof to the west, came off the US coast near Norfolk, Va. There was only high-level cloud with this particular shortwave. Within 6 hours, convection blossomed in the divergent area to the NW of the upper trof, (right over the gulf stream), pressures fell rapidly in the area, and a few hours after that the surface cyclone that had rapidly developed did a 180 , bringing 50 kt winds to Norfolk, with basically zero warning. There's the left hook at work. Now, it could be that all the models are suffering from runaway convective feedback, and the deepening and abrupt track change are overdone. But all the elements are there...its going to be a show.
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Quoting LargoFl:
Im seeing reports of the stores running out of batteries and bottled water already


It wouldn't surprise me.
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1126. pcola57
Don't know if this has been posted yet this AM..
Sorry about the double post if it has.. :)

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Going through town and im seeing people taking their flags/flag poles down and putting their halloween decorations down.... Good idea people
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1123. LargoFl
Quoting AussieStorm:
NJ Gov. Chris Christie also reportedly calling 4 MANDATORY evacs of barrier islands from Sandy Hook-Cape May. Includes Atlantic City casinos
thanks aussie..a good move on his part..waiting to see what NY does now
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1122. LargoFl
Quoting TropicalAnalystwx13:

No. Buoys are showing they literally extend over 400 miles out from the center of Sandy.
not yet anyway..it still has to grow
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NJ Gov. Chris Christie also reportedly calling 4 MANDATORY evacs of barrier islands from Sandy Hook-Cape May. Includes Atlantic City casinos
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1120. LargoFl
Quoting BaltOCane:
in Baltimore here.
People are finally taking this seriously now.
Trying to put away anything that can be thrown in the air.
Sandbags have been given out for the last 18 hours or so for Fels Point and Annapolis residents.
Fingers crossed.
Im seeing reports of the stores running out of batteries and bottled water already
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On a related topic, northern Vietnam is about to get pounded and drenched by Son-tinh, as well as the Chinese provinces of Hainan and Guanxi.
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A truly mammoth hurricane.
Member Since: July 8, 2005 Posts: 259 Comments: 24019
Quoting BDAwx:
Remember that although tropical storm force winds extend up to 450miles away from the center, not everywhere between the storm and 450miles will have tropical storm force winds. These winds will probably be in bands far removed from the center.

No. Buoys are showing they literally extend over 400 miles out from the center of Sandy.
Member Since: July 6, 2010 Posts: 113 Comments: 32033
Quoting CaicosRetiredSailor:


Each run puts the center closer to my house. Hmm. About time to finish the remainder of the outside preps and then the last, but best of all, the beer and wine run.
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in Baltimore here.
People are finally taking this seriously now.
Trying to put away anything that can be thrown in the air.
Sandbags have been given out for the last 18 hours or so for Fels Point and Annapolis residents.
Fingers crossed.
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Thanks FLWeatherFreak.
Going to be interesting to watch.
Let's hope they do the right thing with that.
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1111. LargoFl
folks Think of it like this..just HOW big will this storm be?..tropical storm force winds will be 450 miles from its center...ok..thats not too much huh......look at it THIS way...how many miles is THIS?..I-95...........Virginia- 178 miles
Maryland- 110 miles
Delaware- 26 miles
Pennsylvania- 58 miles
New Jersey- 44 miles (see note)
New York- 29 miles
Connecticut- 118 miles
Rhode Island- 47 miles
Massachusetts- 97 miles
New Hampshire- 17 miles
From virginia to new Hamphshire..all at once
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Quoting wxchaser97:

Hey, you are much closer to Sandy than I will be so for me to be under a category shows how big Sandy will be. Here is the CPC 3-7day hazards outlook.

I didnt think u'd be heavily affected tho... Im suprised that ur in the alert section
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1109. Wiebel
Quoting Wunderwood:


You are correct, however, the wave heights in the ocean mean that water will remain contained in flooded areas for a longer period of time. Wave heights are the catalyst for the destructive flooding that may occur.


Waves need surge to "ride on". And a surge increases the water depth allowing larger waves. Short period wind waves (including swell) are not really related to surge, although the wind that generates both surge and waves is!

Did you know that there are no waves in the center of a CAT 5 hurricane?
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Quoting gulfbreeze:
Is this for real??




are you guys nuts are some in or did not of coffe yet this AM



yes that real why would i be posting some in if it wass not real
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NOAA ‏@NOAA
Are you a new #NOAA Weather Radio owner? Find the SAME codes you need to program your radio here
Link
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1106. BDAwx
Remember that although tropical storm force winds extend up to 450miles away from the center, not everywhere between the storm and 450miles will have tropical storm force winds. These winds will probably be in bands far removed from the center.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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