ATL: SANDY - Remnants - Discussion

[Frank2]

I fear the evacuations came too little, too late. I think a good chunk of the people, after what he said yesterday, are going to ignore them.

I've lived down here for most of my life, but my brother and his family live in coastal New Jersey, and spoke to him last evening - he said that the problem is that many think this will be another Irene, which was pretty significant on Long Island but not anywhere else (until it reached New England) - if the forecast becomes reality the concern from what I've been hearing is not so much the wind and the rain but the surge...

To me, the other problem is the population density - so many people in such a small area (my local trip to the Wal Mart is the same distance as the width of Manhattan - with about 30 times the population), and to evacuate would be a real problem, but the good news is that interior Manhattan island is somewhat elevated, unlike lower Manhattan...

Frank

[Sanibel]

Yeah but there's a lot of people to move and not much space to move them to.

[SouthernBreeze]

can you issue hurricane and tropical storm warnings if a storm is subtropical?

They use Gale & high wind warnings instead

[HurricaneRobert]

This is most un real sight of a lifetime. Such large circulation - yu will ned to use side/bottom scroll bars to view it all
Kidding me??
http://www.ssec.wisc.edu/data/1min/inde ... eight=1300

That's neat. You can see a big difference in convection around the center in the first and last frames.

[tolakram]

Latest, Hi Res

http://img513.imageshack.us/img513/5843/zzsandy.jpg

Live java loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... umframes=5

Rapid scan loop, no java or flash required: http://www.ssec.wisc.edu/data/1min/index.php

[MiamiensisWx]

I am a little disappointed that the latest public NHC advisory does not adequately emphasize what should be drilled into the heads of officials and citizens everywhere--that the storm tide of 4 to 6 feet is, as a surge, going to be significantly higher than the forecasted amounts due to the combination of astronomical high tides and 40-foot waves. Many people do not know the difference between storm surge (which is storm tide + actual tide) and storm tide (which is just the amount of water above the mean high tide). They also do not realize that the large fetch will cause very large waves.

The NHC, in its very own page, explains the difference and offers good graphical illustrations. But the page is buried on the Web site and is not as prominent as it should be--most people see the advisories first and naturally look there for data.

Storm surge is an abnormal rise of water generated by a storm, over and above the predicted astronomical tides. Storm surge should not be confused with storm tide, which is defined as the water level rise due to the combination of storm surge and the astronomical tide. This rise in water level can cause extreme flooding in coastal areas particularly when storm surge coincides with normal high tide, resulting in storm tides reaching up to 20 feet or more in some cases.

http://www.nhc.noaa.gov/surge/

The NHC advisory mentions the combination of the surge and high tides, but only briefly, and fails to emphasize the destructive energy of large waves:

http://www.nhc.noaa.gov/text/refresh/MIATCPAT3+shtml/281457.shtml

I am not bashing the NHC, but this could be an example of cases in which communication needs to be improved. I am afraid that if officials fail to take proactive measures due to insufficient communication, people may blame the NHC for not speaking directly to their questions. Who agrees?

[Ken711]

Once Sandy makes landfall, will the strongest winds be to the SW or NE of Sandy's movement?

[Sanibel]

Convection coverage is good and shows a storm that isn't losing strength.



The worst edge of this should be southeast winds piling water into the New York bight there.

[WeatherGuesser]

I'm seeing a lot of people across the web post comments that while they evacuated for Irene, they will not be this time.

[CrazyC83]

Once Sandy makes landfall, will the strongest winds be to the SW or NE of Sandy's movement?

No significant difference most likely.

[johngaltfla]

can you issue hurricane and tropical storm warnings if a storm is subtropical?

Bastardi has been arguing they should have, but the NHC and NWS have their own program. Unfortunately, I don't think the severity of this storm and its potential are being transmitted to the public enough despite the best efforts of the local NWS offices.

This storm still has a lot of room to strengthen in the next 24 hours or so and that is why I am worried about the outcome.

[SNOW_JOKE]

Now you know how we feel in the UK. Despite systems with extratropical characteristics, aswell as Sting-Jets via RACY the Met Office still refuse to name such systems or put them in any other category outside of a Low.

1987 storm, Glasgow storms of 2011 & 2012, Manchester storm, and so on. All of which had winds exceeding 100mph. imho a categorization system is needed given the increased awareness and frequency of these hybridstorms/hybridcanes.

[Ken711]

Once Sandy makes landfall, will the strongest winds be to the SW or NE of Sandy's movement?

No significant difference most likely.

Thanks. What factors will cause Sandy to lose strength eventually after landfall since this is a hybrid system?

[Frank2]

I'm seeing a lot of people across the web post comments that while they evacuated for Irene, they will not be this time.

Yes, New Yorkers tend to be very stubborn, but being stubborn doesn't count when it comes to storm surge...

Per the comments about the NHC advisory - the public advisory does refer local residents to see statements being issued by their local NWS office, and the individual local statements give the finer details about what to expect...

[WeatherGuesser]

I'm a few hundred miles SSW of Chicago and have been getting sustained winds in the 20s with gusts near 30 for the last couple of days. I wasn't sure it was related to this or just residual from the storm system that passed last week.

[crimi481]

I'm seeing a lot of people across the web post comments that while they evacuated for Irene, they will not be this time.

Yes, New Yorkers tend to be very stubborn, but being stubborn doesn't count when it comes to storm surge...

Per the comments about the NHC advisory - the public advisory does refer local residents to see statements being issued by their local NWS office, and the individual local statements give the finer details about what to expect...

New Yorkers have all the best reasons to be "stubborn" - as well as collectable calm in face of danger

[WeatherGuesser]

Have we set a pressure record yet? I'm still seeing 951.

[Peach]

I'm getting 740 miles of TS winds from the NHC section someone here was kind enough to point out. Is this correct?

[cycloneye]

Have we set a pressure record yet? I'm still seeing 951.

Recon is about to make another pass to see how is the pressure.

[KBBOCA]

In follow up to MiamiensisWX comment about the NHC and communication about the storm surge, I was very concerned last night when there was no specific mention of NY Harbor in the advisory. (if there was, I missed it!)

Similarly, they talked about "significant storm surge" - not a word that conveys danger.

Today's 8 a.m. advisory by Stacey Stewart was MUCH clearer and more direct and I found it much more helpful in outlining the storm surge danger.

Compare Advisory 23:

...SANDY CONTINUING NORTHEASTWARD PARALLEL TO THE COAST OF THE SOUTHEASTERN UNITED STATES...
...STRONG WINDS AND SIGNIFICANT STORM SURGE ARE EXPECTED IN THE MID-ATLANTIC STATES AND SOUTHERN NEW ENGLAND...

STORM SURGE...THE COMBINATION OF A DANGEROUS STORM SURGE AND THE TIDE WILL CAUSE NORMALLY DRY AREAS NEAR THE COAST TO BE FLOODED BY RISING WATERS. THE WATER COULD REACH THE FOLLOWING DEPTHS ABOVE
GROUND IF THE PEAK SURGE OCCURS AT THE TIME OF HIGH TIDE...

NC SOUTH OF SURF CITY...1 TO 3 FT
NC NORTH OF SURF CITY INCLUDING PAMLICO/ALBERMARLE SNDS...3 TO 5 FT
SE VA AND DELMARVA INCLUDING LOWER CHESAPEAKE BAY...2 TO 4 FT
UPPER AND MIDDLE CHESAPEAKE BAY...1 TO 2 FT
OCEAN CITY MD TO THE CT/RI BORDER...4 TO 8 FT
LONG ISLAND SOUND...RARITAN BAY...AND DELAWARE BAY...4 TO 8 FT

Now look at Advisory 24 A:

...SANDY EXPECTED TO BRING LIFE-THREATENING STORM SURGE FLOODING TO THE MID-ATLANTIC COAST...INCLUDING LONG ISLAND SOUND AND NEW YORKHARBOR......WINDS EXPECTED TO BE NEAR HURRICANE FORCE AT LANDFALL...

STORM SURGE...THE COMBINATION OF AN EXTREMELY DANGEROUS STORM SURGE AND THE TIDE WILL CAUSE NORMALLY DRY AREAS NEAR THE COAST TO BE
FLOODED BY RISING WATERS. THE WATER COULD REACH THE FOLLOWING DEPTHS ABOVE GROUND IF THE PEAK SURGE OCCURS AT THE TIME OF HIGH TIDE...

NC SOUTH OF SURF CITY...1 TO 3 FT
NC NORTH OF SURF CITY INCLUDING PAMLICO/ALBEMARLE SOUNDS...4 TO 6 FT
SE VA AND DELMARVA INCLUDING LOWER CHESAPEAKE BAY...2 TO 4 FT
UPPER AND MIDDLE CHESAPEAKE BAY...1 TO 2 FT
LONG ISLAND SOUND AND RARITAN BAY INCLUDING NEW YORK HARBOR...6 TO 11 FT
ELSEWHERE FROM OCEAN CITY MD TO THE CT/RI BORDER...4 TO 8 FT
CT/RI BORDER TO THE SOUTH SHORE OF CAPE COD INCLUDING BUZZARDS BAY...3 TO 5 FT

Which one is the more effective communication tool to those most severely threatened in the NY Metro area?

Had the forecast changed between 11 p.m. and 8 a.m. which allowed Stewart to be more specific? Or was it just better writing and a clearer understanding of how to communicate danger?


Disclaimer: I am so grateful for the NHC and they do an AWESOME job. This is just meant as constructive criticism to help us learn lessons of what could be better next time in terms of communicating storm risk to the general public.