Irene continues to weaken

By: Dr. Jeff Masters , 8:46 PM GMT on August 26, 2011

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Satellite data and measurements from the Hurricane Hunters show that Irene continues to weaken. A 1:32 pm EDT center fix by an Air Force Reserve aircraft found that Irene's eyewall is still gone, and the central pressure had risen to 951 mb from a low of 942 mb this morning. The winds measured in Irene near the surface support classifying it as a strong Category 1 hurricane or weak Category 2. Satellite imagery shows a distinctly lopsided appearance to Irene's cloud pattern, with not much heavy thunderstorm activity on the southwest side. This is due to moderate southwesterly wind shear of 10 - 20 knots. This shear is disrupting Irene's circulation and has cut off upper-level outflow along the south side of the hurricane. No eye is visible in satellite loops, but the storm's size is certainly impressive. Long range radar out of Wilmington, North Carolina, shows that the outermost spiral bands from Irene have moved ashore over North Carolina. Winds at buoy 41004 100 miles offshore from Charleston, SC increased to 47 mph, gusting to 60 mph at 3 pm EDT, with significant wave heights of 25 feet.


Figure 1. MODIS satellite image of Hurricane Irene taken at 11:50 am EDT Friday August 26, when Irene was a Category 2 hurricane with 105 mph winds. The eyewall collapsed several hours before this image was taken, and no eye is apparent. Image credit: a href=http://rapidfire.sci.gsfc.nasa.gov/gallery/ NASA.


Figure 2. Distribution of Irene's wind field at 3:30 pm EDT Friday August 26, 2011, as observed by the Hurricane Hunters and buoys. The right front quadrant of the hurricane had about 90% of the storm's hurricane-force winds (yellow and warmer colors, bounded by the heavy black line between the "50" and "60" knot thin black lines.) Tropical storm-force winds (heavy black like bounding the light blue area) extended out 290 miles from the center of Irene. Image credit: NOAA/AOML/HRD.

Forecast for Irene
With its eyewall collapsed and just 18 more hours over water before landfall, Irene does not have time to build a new eyewall and intensify. The storm is too large to weaken quickly, and the best forecast is that Irene will be a strong Category 1 hurricane at landfall in North Carolina on Saturday. Based on the latest wind analysis from NOAA's Hurricane Research Division (Figure 2) and Irene's continued weakening trend, I predict that the 80-mile section of North Carolina coast to the right of where Irene makes landfall will receive sustained hurricane-force winds of 75 - 85 mph on Saturday at landfall; the 80-mile section of coast to the left will receive 55 - 75 mph winds. High wind shear of 30 knots will begin ripping into Irene Sunday morning when it is near Southern New Jersey, and more rapid weakening will occur. By the time Irene arrives on Long Island Sunday afternoon, it will probably have top sustained winds in the 65 - 75 mph range. However, since Irene is such a huge storm--tropical storm force winds extend out up to 290 miles from the center--it has set a massive amount of the ocean's surface in motion, which will cause a much larger storm surge than the winds would suggest. At 3:30 pm EDT this afternoon, a wind analysis from NOAA/HRD (Figure 2) indicated that the potential storm surge damage from Irene still rated a 5.0 on a scale of 0 to 6. This is equivalent to the storm surge a typical Category 4 hurricane would have. While this damage potential should steadily decline as Irene moves northwards and weakens, we can still expect a storm surge one full Saffir-Simpson Category higher than Irene's winds when it impacts the coast. Since tides are at their highest levels of the month this weekend due to the new moon, storm surge flooding will be at a maximum during the high tidal cycles that will occur at 8 pm Saturday night and 8 am Sunday morning. Wherever Irene happens to be at those times, the storm surge damage potential will be maximized. I continue to give a 20% chance that a 3 - 4 foot storm surge high enough to over-top the Manhattan flood walls and swamp the New York City subway system will occur on Sunday. The latest 11 am probabilistic storm surge map from NHC shows a 20 - 30% chance of a storm surge in excess of 3 feet in New York Harbor (Figure 4.) Keep in mind that these maps are calculated for normal tide level, and this weekend's high tides will be nearly 1 foot above normal.

Insurance company AIR-Worldwide is estimating that insured damages from Irene in the U.S. will be $1.5 - $6 billion. They estimate losses in the Caribbean at $0.5 - $1.1 billion from Irene.


Figure 3. Storm surge heights, in feet above normal tide level, which have a 20 percent chance of being exceeded during the next 3 days.  The graphic is based upon an ensemble of Sea, Lake, and Overland Surge from Hurricanes (SLOSH) model runs using the current National Hurricane Center (NHC) official hurricane advisory. The exceedance heights depend on the historical accuracy of NHCs forecasts of hurricane track, and wind speed, and an estimate of storm size. Image credit: NOAA.


Figure 4. Overall chance that storm surges will be greater than 3 feet above normal tide levels during the next 3 days.  The graphic is based upon an ensemble of Sea, Lake, and Overland Surge from Hurricanes (SLOSH) model runs using the current National Hurricane Center (NHC) official hurricane advisory.  Storm surge probabilities depend on the historical accuracy of NHCs forecasts of hurricane track, and wind speed, and an estimate of storm size. Image credit: NOAA.

Links
For those of you wanting to know your odds of receiving hurricane force or tropical storm force winds, I recommend the NHC wind probability product.

Wunderground has detailed storm surge maps for the U.S. coast.

The National Hurricane Center's Interactive Storm Surge RIsk Map, which allows one to pick a particular Category hurricane and zoom in, is a good source of storm surge risk information.

Wunderblogger Mike Theiss is in Nassau, documenting the storm's impact on the Bahamas.

Internet radio show on Irene at 4:30pm EDT
Wunderground meteorologists will be discussing Hurricane Irene on a special edition of our Internet radio show, the Daily Downpour, today (Friday) at 4:30pm EDT. Shaun Tanner , Tim Roche, Angela Fritz, and Rob Carver will take your questions. The email address to ask questions is broadcast@wunderground.com.

Jeff Masters

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00z NAM takes Irene directly over NYC.
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1351. JamesSA
Oh... Topsail Island! I was looking st somewhere else. That is like GROUND ZERO! Should be an interesting webcam as long as the power stays on! Too bad for the pier.
Member Since: August 17, 2009 Posts: 0 Comments: 579
Link
O.C Md. webcams.Should be a good view tomorrow.
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1349. hahaguy
Quoting tiggeriffic:
high tide charleston, sc at the battery

http://s1209.photobucket.com/albums/cc390/maryalo vestigger/?action=view¤t=082611185529.jpg&ev t=user_media_share

ok...trying to copy the pic didn't work...hope this does


page not found
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high tide charleston, sc at the battery

http://s1209.photobucket.com/albums/cc390/maryalo vestigger/?action=view¤t=082611185529.jpg&ev t=user_media_share

ok...trying to copy the pic didn't work...hope this does
Member Since: September 16, 2007 Posts: 0 Comments: 3650
Quoting Levi32:


That is likely. I can't believe that some streets there are already underwater based on the picture posted here earlier. I would like to know whether that was ocean water flooding a sea-side street or fresh water. I would think it was more likely to be the ocean.


That picture was Canal drive at Carolina Beach. It will flood during a bad rain storm.
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1346. owntime
Quoting Dennis8:


Very good point..Ike gave us TS winds from 8pm until 10am and hurricane force from 1am until 8am and Irene is as large as Ike. We were 50 miles inland 3 miles north of downtown Houston. We got 11 inches of rain between 11pm and 9 am and that was measured in hurricane winds and my wireless gauge was on a fence that blew down! 28.29 on my Davis barometer as the eye cam just east of downtown at 5:30 am September 13, 2008.


I was in Ike also, 290 & Tidwell. It was a bad storm even that far away from the coast. I got my power restored 3 weeks later. Thank goodness for generators and planning ahead.
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XD oz's streaam is priceless "My outside mic has a condom and some monkey fur on it... GREAT AUDIO :D"
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Quoting bassis:

Where are you near





i live in CA am this watching what am seeing on the cams on my laptop and was this saying that things gone way down hill tonight at NC
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1343. ncstorm
Quoting nccanewatcher:


Which beach because some, if not all, of the bridges are closed?


Yeah..if you are talking about wrightsville beach or carolina Beach, the bridges are closed
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1342. 900MB
Quoting AllStar17:
AF308 Mission 29 heading back for another center pass.


Looks like lower pressure readings on approach than last pass..but, i just got Google earth, so I don't know nada! 978mb far out last I saw.
Member Since: June 11, 2006 Posts: 0 Comments: 684
1341. Dennis8
Precipitation 2.10 in Beaufort Irene rainfall
Member Since: August 15, 2008 Posts: 0 Comments: 446
Quoting zawxdsk:
NCStorm - this is a stupid question but give me some help here because I need to get a couple of people out of your area.

Brother and Sister and law live in Wilmington, right on the beach. They were going to go inland as of this morning. I just now heard that they are still there.

Assuming I can't convince them to go - how bad do you expect it there right on the beach?


Which beach because some, if not all, of the bridges are closed?
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Only word I can come up with is BIG!

Member Since: September 8, 2005 Posts: 0 Comments: 3805
AF308 Mission 29 heading back for another center pass.
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Quoting dogsgomoo:


That's really cool! I love seeing the types of structures that actually make it through these storms. So many lessons.


CNN and others news people stayed there after they got trapped on the island.

video
Man Survives Hurricane Ivan in Hurricane-Proof House

'Dome Home' weathers storm
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I'm in Bangkok, and hail from Hampton Roads Virginia....what a beast to snuffle ashore during a kingtide! Hope all the hatches are battened down.
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1334. hahaguy
Quoting padirescu:


Link please?


Link
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Quoting Levi32:


I would say no, because the wind maximum with Irene is fairly wide, and with the eye almost nonexistent, there isn't a small, well-defined region of highest winds, and they extend for quite a ways away from the center. It is tracking slightly east of the forecast track, but your area near the outer banks is not off the hook. You're still going to have to deal with several inches of rain no matter what.


true, but Im feeling alot better now that I was 6 hours ago, weakening and east of track, loving it.
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1332. Patrap
Member Since: July 3, 2005 Posts: 424 Comments: 128348
This is where I have the center.
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Quoting jdjnola:
There are people on the pier! Crazy people!


Link please?
Member Since: September 2, 2008 Posts: 0 Comments: 60
That was honestly the first time I've ever typed "OMG" without being ironic!

NoVaForecaster, what's your forecast for our area?
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Quoting Swpepper:


There were two people on the pier for a brief amount of time. Here's some info about the pier:

Topsail Island's first ocean pier, the Surf City Pier, was originally built in 1948. It has been owned and operated by the Lore family since 1973. Though it has weathered many storms (some better than others), Hurricane Fran destroyed it in 1996. It was totally rebuilt and reopened in August of 1997, looking much like it does today including a few additions. The pier is 937 feet long with a 40-foot octagon at the end.

I can't find any info as to it's height, but 20-25' is the common height. Betcha $20 the two people you saw are either the owners or operators of the pier walking out to check something.

You know, if I owned it, I'd insure it. And tomorrow night would be soon enough to check it and file a claim.
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1327. JamesSA
Quoting TropicalAnalystwx13:


The webcam is located at Topsail Island. To give a perspective, the eye of the storm won't be north of the system until it comes close to making landfall in the OBX.
I was guessing Topsail Island to be at about 33N. You are right, the eye is not yet North of it.

If I have the location right it looks on the satellite like it may be getting the worst of the wind and surge right now and it is taking it pretty well so far. Must be a well built pier!

Do you think it will get worse there?

Member Since: August 17, 2009 Posts: 0 Comments: 579
Quoting Fotograffa:


Is it the storm that will be crazy or you?? Do you realize when the storm arrives those conditions will last 18-21 hours? Are you really ready for that? I hope you'll reconsider your decision. No one is going to help you out once this gets rolling.


very strong words...ill be fine i think..im with three other storm fanatics
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Quoting Fotograffa:


Is it the storm that will be crazy or you?? Do you realize when the storm arrives those conditions will last 18-21 hours? Are you really ready for that? I hope you'll reconsider your decision. No one is going to help you out once this gets rolling.


Just a reminder but once an area starts to receive tropical storm force winds, all emergency services are shut down until after the storm has begun to wind down. You will be helpless if (God forbid) something happens and you need assistance. Make smart decisions.
Member Since: September 24, 2005 Posts: 33 Comments: 9265
Quoting tiggeriffic:
Charleston, SC battery at high tide...look close, you can see the water level on the right is actually higher than the road on the left...no camera tricks people...it really was...by at least 2 feet if not more.


Did you figure out how to post images yet? Really curious to see your pictures.
Member Since: October 16, 2008 Posts: 0 Comments: 544
1323. Levi32
Quoting VAbeachhurricanes:


Levi I feel like its moving way east of forecast, are we off the major hook here in hampton roads?


I would say no, because the wind maximum with Irene is fairly wide, and with the eye almost nonexistent, there isn't a small, well-defined region of highest winds, and they extend for quite a ways away from the center. It is tracking slightly east of the forecast track, but your area near the outer banks is not off the hook. You're still going to have to deal with several inches of rain no matter what.
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1322. Walnut
Quoting muddertracker:


Here's your card....(or body bag)
Shark food.
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Quoting shadoclown45:
isnt the rain in a hurricane a fine mist that falls extremely fast aided by winds, and also i live on staten island on top of grimes hill the second tallest area on staten island i have a view of the hudson/bay area looking torwards sandy hook if i could get a live stream up would anyone watch it?


what i got today wasnt a fine mist...it rained so hard it hurt as i had to run thru it and that was a baby feeder band
Member Since: September 16, 2007 Posts: 0 Comments: 3650
Quoting cindyker:
Are there people on TS Pier!?


There were two people on the pier for a brief amount of time. Here's some info about the pier:

Topsail Island's first ocean pier, the Surf City Pier, was originally built in 1948. It has been owned and operated by the Lore family since 1973. Though it has weathered many storms (some better than others), Hurricane Fran destroyed it in 1996. It was totally rebuilt and reopened in August of 1997, looking much like it does today including a few additions. The pier is 937 feet long with a 40-foot octagon at the end.

I can't find any info as to it's height, but 20-25' is the common height. Betcha $20 the two people you saw are either the owners or operators of the pier walking out to check something.
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1319. swfla
Yes, typical for cameras of that tight, too many people using it at once & using more bandwidth then it can handle. You're all going to have to take turns watching it:-)

Quoting hahaguy:
anyone elses video freezing up?
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1317. Dennis8
Cape Hatteras gust to 63 mph

10:20 PM 80.6 °F 87.1 °F 77.0 °F 89% 29.62 in 1.8 mi ESE 31.1 mph 63.3 mph 0.73 in Rain Light Rain
Member Since: August 15, 2008 Posts: 0 Comments: 446
Quoting dogsgomoo:
Thank you for your answers. You all are awesome.

I'm unsure of how to stress to them that they should leave because they are confident that everything will be fine. They have lived there all their lives. Their parents and grand parents as well.

They seem very confident that the 3 story house they are in will withstand because they are on the Bay side and not the Ocean side. Having seen it, I think it will as well, but...

I've lost the link to the surge reports for Irene and I'd like to post it on their face book page as a last ditch effort to get them facts. Does anyone have that handy?

The thing is, you just don't know which will make it and which won't. Storm surge from Dennis came from the north, the bay side, and took out homes that survived Ivan on Pensacola Beach. And speaking of Ivan, surge took out the interstate bridge, houses on Bayou Chico, and houses at the far north end of Escambia Bay, AFTER crossing the island.

Check the maps and you'll see what I am talking about.

surge forecast
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1315. bassis
Quoting Tazmanian:
things have gone way down hill tonight in NC

Where are you near
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Quoting Levi32:


A note of comfort though from an official that Cantore interviewed is that the structures that have been around for over 100 years, have been around for over 100 years, after all, and had to go through the 1821 hurricane, as well as others that went through the northeast. Chances are they can handle a strong TS or Cat 1, even if it is for a long duration. Hopefully that holds true and the winds don't do any real structural damage to the NYC area.
Levi, I would make an educated guess that the tallest structure in 1821 in NYC was 10, maybe 12 stories. It would have been a rare building that was over 5 stories. It's completely different now. I'm not concerned about the 100 year old buildings. Even then, there wasn't a building taller than 20 stories in the whole city. I'm concerned about all the buildings put up between 1945-1965, many hundreds of them, which have never been subjected to a storm, nor are they built to deal with one.
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Quoting snotly:
people on the pier @ topsail....!!!!!??


Here's your sign....(or body bag)
Member Since: August 16, 2007 Posts: 1 Comments: 2348
CycloneOZ just got hit by hail Link
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Quoting Levi32:
Eye moving just a hair east of due north, right towards the outer banks.



Appears like we can narrow down the landfall point to between the Morehead City/Beaufort/Cape Lookout area and Cape Hatteras. But the exact area where she crosses the coastline is almost irrelevant with the huge swath of tropical storm and hurricane force winds.
Member Since: September 24, 2005 Posts: 33 Comments: 9265
1310. Dennis8
WILMINGTON gust to 58 mph

10:14 PM 73.4 °F - 73.4 °F 100% 29.38 in 1.2 mi NNE 36.8 mph 57.5 mph 0.33 in Rain Heavy Rain
Member Since: August 15, 2008 Posts: 0 Comments: 446
1309. hahaguy
Quoting VAbeachhurricanes:


link???

http://www.surfchex.com/index.php
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Quoting Portlight:


e mail them to yourself...open the email..open the pic...right click on 'copy picture location'.....paste into 'image' below...voila!...oh yea...click 'post comment'


ha ha you got mail back...

portlight...how do i email them to myself on wunderblog lol...look, i just learned last week how to get a link to stick roflmbo
Member Since: September 16, 2007 Posts: 0 Comments: 3650
Quoting Levi32:


That is likely. I can't believe that some streets there are already underwater based on the picture posted here earlier. I would like to know whether that was ocean water flooding a sea-side street or fresh water. I would think it was more likely to be the ocean.


Ocean - All the pictures that we posted were located very near the beach.
Member Since: July 6, 2010 Posts: 113 Comments: 32080
1306. Patrap
Member Since: July 3, 2005 Posts: 424 Comments: 128348
Quoting AllyBama:


no, I saw it too!


link???
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Quoting Levi32:
Here's another cam. I have no idea where it is though.
thank you
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I'm looking for updated rainfall forecasts for the storm as it passes through the DC, NJ and NY areas if anyone can post them. TIA
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Quoting NJcat3cane:
im sticking it out here in Atlantic City even with mandatory evac here..should be crazy


Is it the storm that will be crazy or you?? Do you realize when the storm arrives those conditions will last 18-21 hours? Are you really ready for that? I hope you'll reconsider your decision. No one is going to help you out once this gets rolling.
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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.