ATLANTIC: Hurricane Sandy

[Jeff Snyder]

The problem with reporting "maximum winds" that the NHC provide are that they typically occur over a small area (and often aren't actually ever observed by surface observation stations), and this fact/observation very rarely is communicated properly in the media and on TV. I hope residents of the effected areas don't think that what they're seeing are 90 mph sustained winds with gusts to 110 mph. Current satellite data show a dry slot wrapping around Sandy, putting an end to the heavier precipitation. Radar data from nearby radars (e.g., KDIX) support this observation. KDIX VWP is showing ~100 kt winds at ~4 kft AGL. Typically, since the heavy rain helps to transport the stronger winds above the surface down to near the ground, a reduction in precip rates and coverage would be expected to reduce the potential for the strongest winds to be occur nearer the ground. I don't see why the same wouldn't occur with Sandy. I'd think that gusts near 70 mph are possible near the coast, but Sandy's sustained 90 mph winds will not be measured at the ground. I don't think even gusts to 90 mph will be observed. Heck, there's a good chance that no hurricane-intensity sustained winds will be observed. This is not to say that 60-70 mph gusts will be inconsequential, obviously!

Edit: Current HRD wind analysis. The hurricane-force winds are currently only occurring in a small area S of the center.

 

[Warren Faidley]

Joe Bastardi just noted on Fox News that several eastern coastal areas (including Atlantic Beach region) to be "destroyed" by massive 18ft+ ft storm surges later today and tonight.

W.

 

[Elinor McLennon]

How is storm surge predicted? Im glad its going to be beautiful here in OKC for Halloween...my favorite holiday! TWC saying almost a million already without power.

 

[Warren Faidley]

How is storm surge predicted? Im glad its going to be beautiful here in OKC for Halloween...my favorite holiday! TWC saying almost a million already without power.

The only "official" storm surge prediction I know of (besides localized statements and forecasts) are issued by the NHC as seen here:

http://www.nhc.noaa.gov/refresh/graphics_at3+shtml/211847.shtml?gm_esurge#content

There are several complexities for estimating storm surge, including, but limited to local geography, flood controls, sea depth and tides. When you toss in bays, river inlets, harbors and drainage it becomes even more complex. The main factors I consider are storm movement (fast-slow-direction) and most important, the angle of the storm and strength as it makes landfall. You will have on shore and offshore winds moving water depending on where you end up. I've chased some hurricanes (including Isabel in 93') and ended up too far south. Although the massive waves offshore looked like they would bring in 15 ft. surges , the offshore winds held them back.

I'd be surprised to see a 18ft. storm surge with Sandy. None of the NHC forecasts show that. Regardless, storm surges are very dangerous and nothing to ignore, but cable networks should be ashamed of predicting 20+ foot surges, like I heard over the last hour. These kind of false reports may cause panic and force people to evacuate into other dangers.

W.

 

[MClarkson]

The tide guage near LGA has 12 feet of surge and had been rising pretty fast.

http://tidesandcurrents.noaa.gov/quicklook/data/SANDY.html

And I don't think thats fake. Thats precisely in the spot where models were suggesting highest surge, and bridgeport across the sound is coming up pretty hard too.

 

[Stuart Robinson]

So Sandy is now extra tropical re latest NHC advisory - models had a good handle on this on Saturday.

 

[JoelHamburger]

Just spent a few hours walking around Brooklyn. Around 5:00 I estimated sustained winds of 30 mph with 45-50 mph gust at the Pier 1 which is here: https://plus.google.com/107035512898840687958/about?gl=us&hl=en

The water level was about 16" below the seawall so I'm fairly confident this will be breached in the next few hours.

Currently experiencing estimated 40 mph sustained winds with some fairly strong gusts, maybe 60-65 mph. There are numerous downed trees including one directly in front of my apartment. The doors and windows are rattling so there's some wind here.

hoping against a preventive power shutdown.

anyone out there stay safe.

-j

 

[Warren Faidley]

Looks like post-tropical flooding in NY City will create a mega-expensive disaster, especially to the underground electrical systems. Hard to get accurate reports as street flooding is being confused with damaging surge waves which does not appear to be the case.

W.

 

[Justin Wiley]

Looks like Sandy has now been officially classified as a "SuperStorm".

 

[B Ozanne]

NYC CBS is showing remarkable footage of water flowing into the Battery Tunnel. Lower Manhattan subways are being flooded. Besides the surge, the storm was a real snoozer in my area until around 5pm, then the first rain bands came in. The top of a cedar tree hit my roof, I don't think it did any damage. Pretty scary moment as I was outside watching and my 3 year old was in the room it hit.

The governor of CT just came on TV and urged coastal towns to evacuate to category 4 storm models.

Edit: Local ABC just that zone c in NYC is seeing flooding. They are also reporting that 42nd street south is dark river to river, not sure the video they are showing agrees.

 

[Warren Faidley]

CNN reports 3 feet of water flooding the interior of the New York Stock Exchange. W.

 

[B Ozanne]

CNN reports 3 feet of water flooding the interior of the New York Stock Exchange. W.

NYSE is confirming that is false, a Twitter fueled rumor.

Major evacuation in The Rockaways as fire is consuming row houses partially submerged by flood waters.

 

[Jeff Snyder]

Man, this was a *heck* of a forecast, especially considering it's a 168 hour forecast made when Sandy was a fledgling storm in the southern Caribbean. The ECMWF nailed Sandy almost from the beginning of Sandy's life. When nearly every other model was taking Sandy out to sea, the Euro picked up on the interaction with the intense negatively-tilted trough correctly. This forecast ended up ~12 hours too slow, but that's in the noise for a 168 hour forecast.

 

[MClarkson]

Yup, big win for the euro on this one. It pretty much locked in on NJ a week ago, and it took the GFS a few more days to flip to that solution.

 

[Joshua T. Clark]

Has anyone heard of Rev Michelle Hopkins? Just watched a video and it looks like the tin foil hat crowd is all over this. More of the ridiculous HAARP stuff.