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Cane Sandy Obs-New England


Damage In Tolland

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the USGS numbers from the temporary gauges they put up on Staten Island are incredible, some 13- 16 footers in there. Surprised NOAA did not reference them.

Well they don't directly measure surge. Only know surge if you know what the astronomical tide (above/below a certain datum) would be and when.

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Stamford surge was 11.24 feet and their peak tide was 11 feet.

Had 11 feet of surge occurred at high tide their peak storm tide would have been like 17 feet or something ungodly.

yea I see what you mean know. unfortunately looks like there are no tide level stations on SI so the surge true value will not be known. I did speak to a contractor today who is rebuilding a Chiller plant on SI and said the water line was 17 feet in the building, amazing.

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yea I see what you mean know. unfortunately looks like there are no tide level stations on SI so the surge true value will not be known. I did speak to a contractor today who is rebuilding a Chiller plant on SI and said the water line was 17 feet in the building, amazing.

They are able to figure it out though. So the USGS can give you the data eventually... I'm not sure if they have it posted online. I know after Irene they gave me a list of all the tide data with surge included based on predicted astro tide.

The folks at USGS in East Hartford are awesome. Very helpful.

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I'll have to look at what the highest BOS harbor surge is. It's obviously not that high considering it's not prone to surges from the east, but the big Feb retro gale of 2010 gave the buoy the biggest surge...bigger than Bliz of '78 I believe.

It's amazing how much wind direction and wave height/period plays a big role in dmaage potential too. More than just tide level. Unfortunately this isn't something that is particularly easy to quantify in LIS but I want to spend some time working on it.

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It's amazing how much wind direction and wave height/period plays a big role in dmaage potential too. More than just tide level. Unfortunately this isn't something that is particularly easy to quantify in LIS but I want to spend some time working on it.

Take a house on the water for example. Say the surge from the ocean comes 2' up the house. Yes there will be wave action battering the house, but friction from shallow water depth will chew up the wave height. But, throw in water that comes up 8'. While I don't have the data...I would think there is some sort of a logarithmic or exponential relationship to these wave heights. 25' breakers certainly won't get chewed up by 8' water depth like that would with a 2' water depth.

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Take a house on the water for example. Say the surge from the ocean comes 2' up the house. Yes there will be wave action battering the house, but friction from shallow water depth will chew up the wave height. But, throw in water that comes up 8'. While I don't have the data...I would think there is some sort of a logarithmic or exponential relationship to these wave heights. 25' breakers certainly won't get chewed up by 8' water depth like that would with a 2' water depth.

well there is a formula to calculate at what water height a wave of x feet will break.

a wave breaks in water approx 1.3 times it's height.

so a 20 foot wave breaks in about 25 feet of water (26ft) . if the wave is traveling over a gradually decreasing ocean bottom then the wave will break a bit more crumbly , if it travels from say 50 feet water and then encounters a more sharp decrease in the angle of the bottom, by a reef, the wave will tend to 'peel'

so i think , using your example above when the water level rises around a structure the potential wave heights impacting that structure (assuming there is a storm , and a open enough ocean that is not impeding incoming swells) definitely increases with the water level. 2 feet of water could sustain 1.5 feet breaking waves while 8 feet can sustain 6 feet breaking waves, roughly.

also somewhat related to ryan's point, swell period definitely effects the height (potential) of a breaking wave at the shore. a 6 foot swell with a period of 10 seconds not only (has less potential to travel great distances without decaying) and also will only produce a wave of say 8 feet. while a 6 foot swell with a period of 16 seconds (holds more of it's energy below the ocean) which also limits the decay (over hundreds and hundreds of miles traveled) but also the added energy below the surface helps to produce a expontentially large break wave at the beach (then it's swell height in the open ocean). a 6 foot swell with a period of 16 seconds can produce a breaking wave of 15 feet....so the greater the period in a swell the more energy below the surface which gets propogated upward as the wave reaches shallower water, "feels the bottom" slows down and builds in height.

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Huge announcement from NHC today with an admission that they did not handle Sandy correctly wrt warnings. Check out new article on accuwx website.

I'm shocked at how quickly the policy change and admission of error occurred.

Indeed. I'm still mad there were no hurricane warnings. At least they admit it, though.

http://www.accuweather.com/en/weather-news/breaking-nhc-modifies-hurrican/2379553

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Indeed. I'm still mad there were no hurricane warnings. At least they admit it, though.

http://www.accuweather.com/en/weather-news/breaking-nhc-modifies-hurrican/2379553

I'm guessing they know what will come out from either the SA or FOIA requests would be pretty ugly.

Already we are seeing bloomberg's people throw Nws under the bus (unwarranted) and NJ Transit doing it too (unwarranted as well). Still I'm guessing they're trying to get in front of the story as it evolves saying they've already taken corrective action.

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I'm guessing they know what will come out from either the SA or FOIA requests would be pretty ugly.

Already we are seeing bloomberg's people throw Nws under the bus (unwarranted) and NJ Transit doing it too (unwarranted as well). Still I'm guessing they're trying to get in front of the story as it evolves saying they've already taken corrective action.

links? did anyone find out who gave Bloomberg that Sat presser info?

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I'm guessing they know what will come out from either the SA or FOIA requests would be pretty ugly.

Already we are seeing bloomberg's people throw Nws under the bus (unwarranted) and NJ Transit doing it too (unwarranted as well). Still I'm guessing they're trying to get in front of the story as it evolves saying they've already taken corrective action.

I still think the biggest issue is not whether tropical headlines should or shouldn't have been in effect (for the record I think they should have been), but rather how the NWS communicates the threat. Clearly, we are not as effective as we think in communicating the non-tropical threat to the Northeast public.

Now I think they've corrected too far in the other direction. Carrying tropical headlines well past any real tropical threat could be counterproductive to getting the public to react (cry wolf syndrome). Hopefully, it is reserved for the "post-tropical" hybrids, such as Sandy. I think rather than fixing the issue at hand (communication, reaction, preparedness, etc.) we are really just covering our asses because of one event. I don't see what's wrong with saying our forecast was great, our communication was ultimately lacking what it could have been, and moving forward from there.

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