Irene sends 4.5 foot storm surge up Chesapeake Bay

By: Dr. Jeff Masters , 12:45 AM GMT on August 28, 2011

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The eye of Hurricane Irene is back over water, after the hurricane completed a 11-hour crossing of eastern North Carolina. Irene came ashore over Cape Lookout, North Carolina at 7:30 am EDT this morning as a Category 1 hurricane with 85 mph winds. The Cedar Island Ferry Terminal measured sustained winds of 90 mph, gusting to 115 mph at 7:19am, as measured by a Department of Transportation official. I suspect this measurement came when a thunderstorm near Irene's center collapsed, sending a powerful downburst to the surface. A trained spotter on Atlantic Beach, NC measured sustained winds of 85 mph, gusting to 101 mph at 10:35 am. The Hurricane Hunters measured 80 mph winds over water at the time of landfall. However, no regular weather station or buoy has measured sustained hurricane force winds in Irene, with the highest winds being 67 mph at the Cape Lookout, North Carolina buoy as Irene made landfall. Winds have peaked along the coast of Virginia, where sustained winds of 61 mph were observed at 6 pm EDT at Chesapeake Bay Light. Irene's passage over land weakened the storm slightly, and satellite loops show more dry air has wrapped into the storm. The radar presentation of Irene visible on the Norfolk, VA radar is still very impressive--Irene is dropping torrential rains over a huge area--but there is much less rain over the storm's southeastern quadrant, over water. Radar-estimated rainfall shows a 50 mile-wide band of 8+ inches of rain has fallen from where Irene made landfall at Cape Lookout, North Carolina, northwards to Dover, Delaware. Some isolated amounts of 15+ inches may have fallen, according to the radar estimates. Bunyan, NC has received 14.00" so far, and the towns of Washington, New Bern, Grifton, Newport-Croatan, Wonona, NC, all received more than ten inches. Norfolk, Virginia had received 7.73" as of 7pm EDT, and Suffolk, Virginia, 8.00".


Figure 1. True-color MODIS image of Hurricane Irene over North Carolina taken at 11:35 am EDT August 27, 2011. At the time, Irene was a Category 1 hurricane with 85 mph. Image credit: NASA.

Storm surge damage from Irene
The storm surge and wave action from Irene is likely to cause the storm's greatest damage. High tide is near 7 - 8 pm EDT tonight, meaning that the storm surges occurring now will be some of Irene's most damaging. The highest surges measured at any of NOAA's regular tide gauges at 8 pm were 4.5 feet at Sewells Point in Norfolk Virginia and Oregon Inlet, NC. Higher surges are occurring father inland where narrow inlets funnel the storm surge to higher elevations. It remains unclear if the ocean will overtop Manhattan's sea wall at The Battery Sunday morning during the 8 am high tide. Latest storm surge forecasts from SUNY Stony Brook predict a peak water level of 2.4 meters above Mean Lower Low Water (MLLW) at 7:15 am Sunday, which would put the ocean right at the top of the sea wall. Presumably, waves from the hurricane's winds would then push some water over the top of the wall, but it is uncertain whether or not this would cause significant flooding. The storm surge was already 1 foot at 8 pm tonight. Storm surge flooding continues to be a major concern all along the coast of Long Island Sound; I recommend the SUNY Stony Brook storm surge page for those interested in looking at observed and predicted storm surge levels along coast New Jersey, New York, and Connecticut.


Figure 2. Storm surge at Sewell's Point in Norfolk, Virginia as of 8 pm EDT Saturday August 27, 2011. The green line is the storm surge, which is the difference between the observed water level (red line) and what the water level should have been without the hurricane (blue line). At 8 pm, the storm surge was 4.5 feet. Image credit: NOAA Tides and Currents.


Figure 3. Distribution of Irene's wind field at 6:30 pm EDT Saturday August 27, 2011, as observed by the Hurricane Hunters, land stations, and buoys. The right front quadrant of the hurricane had all of the storm's shrinking hurricane-force winds (yellow and orange colors.) Tropical storm-force winds (heavy black like bounding the light blue area) extended out 290 miles from the center of Irene over water, but very few areas of land were receiving tropical storm force winds. Image credit: NOAA/AOML/HRD.

Wind damage
The emergence of Irene's eye over water will slow the storm's rate of weakening, but the storm is under too much wind shear to allow it to intensify. The latest wind distribution map from NOAA's Hurricane Research Division (Figure 3) shows that all of Irene's hurricane-force winds are on the storm's east side, and also the large majority of the tropical storm-force winds. When Irene makes its 2nd landfall on Long Island, NY on Sunday, coastal locations to the right of the eye will likely experience top sustained winds of 50 - 60 mph. Coastal areas of Maryland, Delaware, New Jersey, and the New York CIty area will mostly see top winds in the 40 - 55 mph range, since they will be on the weaker left side of the storm. Winds on the upper floors of skyscrapers will be up to 30% higher, but I expect there will be only isolated problems with New York City skyscrapers suffering blown out windows. The winds from Irene in New York City will be no worse than those experienced during some of the city's major Nor'easter winter storms of the past twenty years.

Tornadoes
Four tornadoes have been spawned by Irene, two in coastal North Carolina last night, and two in coastal Virginia today. At least two homes have been destroyed, and ten others damaged by the tornadoes. NOAA's Storm Prediction Center has issued a tornado watch for all of coastal Delaware, New Jersey, New York, and Connecticut.

Links
Our Weather Historian, Christopher C. Burt, has an excellent post on Historic Hurricanes from New Jersey to New England.

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.

Jeff Masters

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Quoting KarenRei:
Anyone watching CNN? When the reporters in NYC were informed that they should be in the worst conditions Irene is going to throw at them (when it was only a light rain with almost no wind), it got *really* awkward ;) They were in total disbelief, lots of awkward pauses as they tried to come to grips with what they were told, then they cut to commercial ;) Less than a minute later they come back with a clip from Jersey where it's actually bad.


I think it's the first time I've ever seen Anderson speechless.
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1036. smuldy
Quoting KarenRei:
Anyone watching CNN? When the reporters in NYC were informed that they should be in the worst conditions Irene is going to throw at them (when it was only a light rain with almost no wind), it got *really* awkward ;) They were in total disbelief, lots of awkward pauses as they tried to come to grips with what they were told, then they cut to commercial ;) Less than a minute later they come back with a clip from Jersey where it's actually bad.
it could get bad and it is where john king is but i swear that other girl got bored and piled a little sand on the board walk and moved some benches lol
Member Since: July 23, 2010 Posts: 0 Comments: 524
Quoting JLPR2:
Time to compare the...

EURO:

And the GFS:



Ohhhhhh stop it! Not again. :(
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1033. smuldy
let me say this is a dangerous storm, but the wcbs affiliate field reporter on asbury park should get a nomination for best supporting actress cause while it could very well deteriorate where she is later, and greatly, she really tried to make an inch of water where she is seem terrifying lol
Member Since: July 23, 2010 Posts: 0 Comments: 524
Anyone watching CNN? When the reporters in NYC were informed that they should be in the worst conditions Irene is going to throw at them (when it was only a light rain with almost no wind), it got *really* awkward ;) They were in total disbelief, lots of awkward pauses as they tried to come to grips with what they were told, then they cut to commercial ;) Less than a minute later they come back with a clip from Jersey where it's actually bad.
Member Since: September 7, 2007 Posts: 1 Comments: 937
1030. WxLogic
Good Morning...
Member Since: August 14, 2008 Posts: 4 Comments: 4928
1029. smuldy
Quoting dewfree:
no one fail us .these things are still being studied as far as i know.

the ULL question was just that a question .it didnt have anything to do i will lay down for alittle while .enjoyed it
dew
idk you seem informed in your questions or i wouldnt have plused one post to get you off the troll list and the night crew seems better here now anyway especially with atmos and misswx just still feel guilty f5ing profit here after what they did to chief last year but when something this weird happens i want to see the take levi and kman have on it and do like hearing the take of miami09 and tampaspin groth keep and others im forgetting now, and this really is one unique storm. nhc has done a better job than anyone with this, and kudos to them especially when models seemed to say otherwise, just amazing they were both right. and the one thing on katrina is yes irene could break it, but were it a cat 2 landfall and broke it in maine, not a shock, but breaking it over open water without a true landfall just a graze of eastern NC, that makes it shocking.
Member Since: July 23, 2010 Posts: 0 Comments: 524
The pressure at the North Beach Haven station, right where she made official landfall, dropped as low as 28.34 inches, or 959.7 mb.
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Quoting atmosweather:


Just looked at the best track from the post-season report and you are correct, it was adjusted down to 961 mb at 8PM 08/29/05. So Irene may still break or tie that.


Regardless of whether she does or not, she's one very remarkable storm.

Generally the only time you get 961mb with sustained winds just above hurricane force are in strong extratropical systems.

Perhaps her inner dynamics - while warm core - are similar to an extratropical storm hence the apparent pressure to wind dysfunctional ratio.
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Quoting Cotillion:


According to Wunderground, Katrina was 961mb as a tropical storm.


Just looked at the best track from the post-season report and you are correct, it was adjusted down to 961 mb at 8PM 08/29/05. So Irene may still break or tie that.
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1025. dewfree
no one fail us .these things are still being studied as far as i know.

the ULL question was just that a question .it didnt have anything to do with low pressure and low winfield at ground level . a remark was made about both the NHC and the guidence being right at the same time . I think the ULL is part of the reason for guidence having a spread ,but I was wondering as to why the ULL went one way and the tropical system went another .what madem go different directions.ussually a steering current influinces both .
Was just curious as to why it went one way and the storm went another .

I always have more question then answer .it is a very bad habbit of mine to speak my opinion rather then askquestion because i came up around older men that didnt want to answer question ,so the only way I could get out of them answers to question is to say what i thought right or wrong, someone somewhere will answer.
that is just a very bad habbit and im sorry for that .
thanks again for taking the time to answer and or repeal my thoughts on the issue .have a good morn think i will lay down for alittle while .enjoyed it
dew
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Over 140,000 outages in CT so far. Highest gust so far is 63MPH in Bridgeport, CT
Member Since: November 17, 2010 Posts: 11 Comments: 527
Quoting atmosweather:
Two historical notes for Irene's central pressure:

1. Irene's maximum sustained winds at landfall in North Carolina were 85 mph, and she had a pressure of 952 mb. But as the much smaller Hurricane Charley of 2004 approached landfall in South Carolina, he had the same 85 mph maximum winds, but his central pressure was 993 mb.

2. If Irene weakens to a tropical storm with a minimum pressure below 965 mb, she will break the Atlantic Basin record for the lowest central pressure measured in a tropical storm, set by Hurricane Katrina while over eastern Mississippi.


According to Wunderground, Katrina was 961mb as a tropical storm.
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1022. smuldy
Quoting atmosweather:
Two historical notes for Irene's central pressure:

>2. If Irene weakens to a tropical storm with a minimum pressure below 965 mb, she will break the Atlantic Basin record for the lowest central pressure measured in a tropical storm, set by Hurricane Katrina while over eastern Mississippi.
and that would be possible before she makes a true landfall which would be just amazing
Member Since: July 23, 2010 Posts: 0 Comments: 524
Two historical notes for Irene's central pressure:

1. Irene's maximum sustained winds at landfall in North Carolina were 85 mph, and she had a pressure of 952 mb. But as the much smaller Hurricane Charley of 2004 approached landfall in South Carolina, he had the same 85 mph maximum winds, but his central pressure was 993 mb.

2. If Irene weakens to a tropical storm with a minimum pressure below 965 mb, she will break the Atlantic Basin record for the lowest central pressure measured in a tropical storm, set by Hurricane Katrina while over eastern Mississippi.
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1020. Seastep
Surge is about 3.5ft at The Battery approaching high tide.

Link
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1019. smuldy
Quoting dewfree:
Does the tropical systems not usually have with them somewhere a ULL and do they not ussually go the way of it
no a ULL is completely independent of a tropical system, that said all they do is usually increase shear, place due north and create an anti cyclone, or weaken the ridging ahead of its path and create a weakness to pull it. The ULL should not usually influence pressure outside of ensemble maps.
Member Since: July 23, 2010 Posts: 0 Comments: 524
Here's the website - it's working for me.... http://www.njsurfer.com/
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Quoting dewfree:
it will certainly be interesting to say the least to hear what the NHC comes up with .So many people were surprised by it and im sure they are not going to get out of explaining it to us .
that was my thought on the issue .this has happened one other time .i cant remeber exactely when it was but it has happened before .thanks for your opinion on the subject.and for taking the time to let me know what you think .
dew


you make it seem as if the NHC failed us and need to explain themselves.
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1016. dewfree
Does the tropical systems not usually have with them somewhere a ULL and do they not ussually go the way of it
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1015. Seastep
Here's another long beach cam.

Only plays for a few seconds before you have to restart it. Surf's up.

Link
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Quoting NJNorEaster:
First light on the ocean at Monmouth Beach, NJ

Link

It aint working for me. Here is a cam at Long Beach, NY.
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1013. smuldy
Quoting dewfree:
it will certainly be interesting to say the least to hear what the NHC comes up with .So many people were surprised by it and im sure they are not going to get out of explaining it to us .
that was my thought on the issue .this has happened one other time .i cant remeber exactely when it was but it has happened before .thanks for your opinion on the subject.and for taking the time to let me know what you think .
dew
NHC essentially had it right more often than not. I gave up fighting with globals last year when persistence appeared (GFS and ECMWF ayway track aside) and that is what made this so interesting as both the bulk of NHC intensity forecasts were right AND the globals were right even though they seemed to fly in the face of each other
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First light on the ocean at Monmouth Beach, NJ

Link
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NOTE...MORE SO THAN WITH MOST STORMS...THE WINDS WITH IRENE INCREASE SHARPLY WITH HEIGHT ABOVE THE SURFACE.

AS IRENE MOVES THROUGH AREAS WITH HIGH-RISE STRUCTURES... THESE BUILDINGS COULD EXPERIENCE WINDS SIGNIFICANTLY STRONGER THAN THE SURFACE WINDS.

WINDS AT THE 30-STORY LEVEL WILL LIKELY BE 20 PERCENT HIGHER THAN AT THE SURFACE...AND WINDS 80-100 STORIES UP COULD BE ABOUT 30 PERCENT HIGHER THAN AT THE SURFACE.

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1010. dewfree
it will certainly be interesting to say the least to hear what the NHC comes up with .So many people were surprised by it and im sure they are not going to get out of explaining it to us .
that was my thought on the issue .this has happened one other time .i cant remeber exactely when it was but it has happened before .thanks for your opinion on the subject.and for taking the time to let me know what you think .
dew
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1009. dewfree
wel it didnt inhibit the wind field as you said at or above 4000 ft .could it not have been atleast some excuse for what happened with this storm
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00
WTNT64 KNHC 280938
TCUAT4

HURRICANE IRENE TROPICAL CYCLONE UPDATE
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
540 AM EDT SUN AUG 28 2011

...IRENE MAKES LANDFALL ALONG THE COAST OF NEW JERSEY NEAR LITTLE
EGG INLET...

DATA FROM NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATE THAT THE
CENTER OF HURRICANE IRENE MADE LANDFALL NEAR LITTLE EGG INLET NEW
JERSEY AROUND 535 AM EDT...0935 UTC. THE ESTIMATED INTENSITY OF
IRENE AT LANDFALL WAS 75 MPH...120 KM/H...CATEGORY ONE ON THE
SAFFIR-SIMPSON HURRICANE WIND SCALE.

NEAR THE TIME OF LANDFALL...A NATIONAL OCEAN SERVICE STATION IN
ATLANTIC CITY NEW JERSEY REPORTED A PRESSURE OF 960.3 MB...28.36
INCHES.


SUMMARY OF 535 AM EDT...0935 UTC...INFORMATION
------------------------------------------------- -
LOCATION...39.4N 74.4W
ABOUT 10 MI...15 KM ESE OF ATLANTIC CITY NEW JERSEY
ABOUT 100 MI...165 KM SSW OF NEW YORK CITY
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...NNE OR 20 DEGREES AT 18 MPH...30 KM/H
MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES

$$
FORECASTER BRENNAN
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1007. smuldy
Quoting dewfree:
very good answer. i believe you just contributed to the answer .

it is my idea that just after turning to the north this storm delt with a boundary and then right before lanfall NC again . and just after again and the reason Irene slowed down was there were and still is a boundary to the north of the storm.
Not to sound stupid or technical iether .this is my thinking point on the issue .
i believe all of the above .
Also think if there is a bounday to the east and one to the west and of corse on one side of the boundary has lower pressure then the other meaning pressure is low because of the one to the east and the other to the west must have a lower pressure reading ,then would it not make sence that she dirrived part of her pressure from that and as far as wind is concerned would the boundaries themselves not inhibit wind field????? that is my thinking on it .
dew
well the wind field is actually quite large, which would make sense as a storm that is weakening loses its strongest winds and tends to flatten out and expand, but the windfield has been large with Irene from the get go as she was both large and displaced; but she is surrounded by high pressure to her east and some high pressure to her west (though less so) and so the gradient should still be larger than it is appearing, even if it is dry air, the dry air made her eyewall collapse and prevented her from churning as much and mixing down to the surface and keeping her lopsided, i just have no idea how that did not result in a significant and rapid rise in central core pressure. (modified to say i was talking about atmospherics at the 500mb level as to the pressure differences not the 850mb)
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Quoting dewfree:
very good answer. i believe you just contributed to the answer .

it is my idea that just after turning to the north this storm delt with a boundary and then right before lanfall NC again . and just after again and the reason Irene slowed down was there were and still is a boundary to the north of the storm.
Not to sound stupid or technical iether .this is my thinking point on the issue .
i believe all of the above .
Also think if there is a bounday to the east and one to the west and of corse on one side of the boundary has lower pressure then the other meaning pressure is low because of the one to the east and the other to the west must have a lower pressure reading ,then would it not make sence that she dirrived part of her pressure from that and as far as wind is concerned would the boundaries themselves not inhibit wind field????? that is my thinking on it .
dew


The interaction with the surface boundary (it's a stalled out occluded front just inland parallel to the coastline) would help keep the deep pressure and also maintain the very broad pressure gradient, but it would not inhibit the wind field since the storm extends a lot higher in the atmosphere than the surface boundaries.
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92L looking pretty good...

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A MADIS station at North Beach Haven just reported a barometric pressure of 28.40 inches Hg, which is 961.7 mb...but with winds of 40 mph. So the minimum central pressure is most likely is STILL lower than 960 mb.
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1003. smuldy
Quoting atmosweather:


that's why her pressure has started to rise slightly more significantly in the last 6-12 hours (still only around 9 mb).
ya i saw that her vorticity was slightly displaced i just really thought either the globals would be wrong and the pressure would rise due to dry air entrainment or that her eye would reform even in water temps that didnt support it and the winds would match up; the one thing i never thought is that it would manage to both maintain this low pressure and yet still weaken, it is mystifying and i cant wait for the post storm analysis from the NHC as they really were spot on in their initial assessment of strength before wavering after model persistence and then coming back after she started to weaken.
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1002. dewfree
very good answer. i believe you just contributed to the answer .

it is my idea that just after turning to the north this storm delt with a boundary and then right before lanfall NC again . and just after again and the reason Irene slowed down was there were and still is a boundary to the north of the storm.
Not to sound stupid or technical iether .this is my thinking point on the issue .
i believe all of the above .
Also think if there is a bounday to the east and one to the west and of corse on one side of the boundary has lower pressure then the other meaning pressure is low because of the one to the east and the other to the west must have a lower pressure reading ,then would it not make sence that she dirrived part of her pressure from that and as far as wind is concerned would the boundaries themselves not inhibit wind field????? that is my thinking on it .
dew
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Quoting smuldy:
Ok I consider myself fairly informed on tropical systems, as I'm pretty smart and have been following them off and on in the 6 years I have spent at least part of my year in SFL, and I get that what has kept Irene in check has been the warm dry continental air she has been ingesting since moving north of the Bahamas, but I guess my question is just how is this storm able to maintain a pressure below 960mb and barely support max sustained winds in the 75-80mph range? I mean winds are caused by differences in the pressure gradient, and without a solid core to mix out the air to the upper levels I am not shocked that wind speeds are where they are, but how in the he11 is she maintaining such a low core pressure? The models saw this low pressure coming and I sure thought that would mean cat 3 to NC and cat 2 to NE, and didn't question it since her outflow was so strong. But how is it possible that both her pressure has remained so low and yet her eye has collapsed and her winds are not (relatively speaking) high? Shouldn't the pressure differences alone mix the wind down to the surface? And if not shouldn't the pressure begin to rise? Is it just the size of this system? How can a warm core system do this? Don't mean to take away time from anyone being directly influenced by this storm as I grew up in CT and still have family in RI, and everyone in the region please watch out as this is a slow moving storm, but anyone more knowledgeable than me willing to take a crack at how this can be happening?



I'm not a met, but apparently there are baroclinic features to Irene, now. A tropical storm/nor'easter monster mutant hybrid, if you like.
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1000. dewfree
But i know the answer to that question in detail or atleast have my on opinion to it an will be wtching the blog to see if anyone else even gets close .
Of corse i would just tell ya but that would give it away and it is just my opinion or idea at this point .

I have enjoyed listening to your post and your concerns on the issue . love the links and repost .
i think that everyone here on this blog has something that they contribute wether they even know or not .
we have all heard stories about things that has happened like this one :
bus went under a bridge and because it was too high got stuck . engineers thought about the problems and could only come up with cutting the bus into .
A 7 year old boy come along and ask them /;why dont you just let the air out of the tires.
dont you know them fellas felt dumb.the thing is ,everyone has something that they can contribute !
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Quoting smuldy:
Ok I consider myself fairly informed on tropical systems, as I'm pretty smart and have been following them off and on in the 6 years I have spent at least part of my year in SFL, and I get that what has kept Irene in check has been the warm dry continental air she has been ingesting since moving north of the Bahamas, but I guess my question is just how is this storm able to maintain a pressure below 960mb and barely support max sustained winds in the 75-80mph range? I mean winds are caused by differences in the pressure gradient, and without a solid core to mix out the air to the upper levels I am not shocked that wind speeds are where they are, but how in the he11 is she maintaining such a low core pressure? The models saw this low pressure coming and I sure thought that would mean cat 3 to NC and cat 2 to NE, and didn't question it since her outflow was so strong. But how is it possible that both her pressure has remained so low and yet her eye has collapsed and her winds are not (relatively speaking) high? Shouldn't the pressure differences alone mix the wind down to the surface? And if not shouldn't the pressure begin to rise? Is it just the size of this system? How can a warm core system do this? Don't mean to take away time from anyone being directly influenced by this storm as I grew up in CT and still have family in RI, and everyone in the region please watch out as this is a slow moving storm, but anyone more knowledgeable than me willing to take a crack at how this can be happening?


That's a question that none of have really been able to answer...it's pretty hard to comprehend that she could maintain a pressure below 960 mb all the way from the Bahamas to southern New Jersey without an actual eyewall or even a central core. Levi and I talked about this last night and I know we are both stunned by this because it's never really happened before in our experiences. My only educated guess would be that because her energy is so spread out and her area of maximum winds is unbelievably broad AND far from the center, it was probably preventing any air from flowing into the center and creating subsidence and higher central pressures. RECON continuously found a center with saturated air at all levels of the atmosphere. Then when the southern portion of the convection basically waned and died out today and this evening, she couldn't really keep the air from blowing into her center anymore, and that's why her pressure has started to rise slightly more significantly in the last 6-12 hours (still only around 9 mb).
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998. JLPR2
Irene is one weird storm... O.o
At least it should be gone soon.

Also, I doubt that what the GFS shows materializes. It doesn't develop 92L, instead now it develops the one behind it. I don't see why 92L wouldn't develop.

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Ok I consider myself fairly informed on tropical systems, as I'm pretty smart and have been following them off and on in the 6 years I have spent at least part of my year in SFL, and I get that what has kept Irene in check has been the warm dry continental air she has been ingesting since moving north of the Bahamas, but I guess my question is just how is this storm able to maintain a pressure below 960mb and barely support max sustained winds in the 75-80mph range? I mean winds are caused by differences in the pressure gradient, and without a solid core to mix out the air to the upper levels I am not shocked that wind speeds are where they are, but how in the he11 is she maintaining such a low core pressure? The models saw this low pressure coming and I sure thought that would mean cat 3 to NC and cat 2 to NE, and didn't question it since her outflow was so strong. But how is it possible that both her pressure has remained so low and yet her eye has collapsed and her winds are not (relatively speaking) high? Shouldn't the pressure differences alone mix the wind down to the surface? And if not shouldn't the pressure begin to rise? Is it just the size of this system? How can a warm core system do this? Don't mean to take away time from anyone being directly influenced by this storm as I grew up in CT and still have family in RI, and everyone in the region please watch out as this is a slow moving storm, but anyone more knowledgeable than me willing to take a crack at how this can be happening?
Member Since: July 23, 2010 Posts: 0 Comments: 524
humm , ok most will wait untill it is explained to them and then they will come up with someone elses original idea.i was just curious.

The answer without giving it way is she couldnt!
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Quoting TampaTom:
What I wouldn't give for a working webcam in Cape May, NJ right now...

Eye appears to be due east, pressure is way down, reports of water already across the beachfront road...

VERY good thing my mom evacuated. Where she is in Pennsylvania lost power late last night..

This is a good link, everyone should bookmark it. Includes a Cape May traffic Camera

I was watching this webcam and in the distance behind the flashing beacon light there was lights on, about 1 minute ago they all went poof.
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Quoting dewfree:
Im curious ,

With low central pressure in Irene .is there anyone here ;that can explain why the wind field did not correspond to the low central pressure ?
of corse i have my on ideas.
i will await your answers >
dew


I see two main reasons, one is that her central core including her eyewall were never really truly organized even when she was intensifying into a Category 3 storm...there was always a slightly variable wind pattern found by the Hurricane Hunters both at the surface and at flight level. This makes it difficult for a storm to produce stronger surface winds and bring them down from flight level...remember, there were many dropsondes that measured very intense winds over 130 mph in the 2,000-4,000 foot range. The second is simply because of her incredibly large circulation envelope, and the fact that after her original eyewall replacement cycle, her area of maximum wind never retreated closer to the center any distance lower than around 50 miles from it. That kind of a wind profile helped expand and spread all of her convective energy over a larger area, thus making it harder for her winds to catch up to the incredibly deep central pressure.
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i also would like to know if any of you can explain why Irene slowed down ?
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Areas of northern New Jersey have now reached and passed the 6 inch mark for total rainfall. This area is particularly flood prone right now with many rivers and estuaries already near flood stage from the recent heavy rainfall. Still a long way to go for those folks and the NYC/Long Island area.
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Im curious ,

With low central pressure in Irene .is there anyone here ;that can explain why the wind field did not correspond to the low central pressure ?
of corse i have my on ideas.
i will await your answers >
dew
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Quoting WatchingThisOne:


You're right, I was looking at an old forecast point, not a center fix.

Apologies for any confusion - haven't been getting enough sleep through this.

Really appreciate your posts, Atmos.


Lol believe me I understand that...not a lot of sleep for me either these past few days with a work/blog/work/blog continuous cycle. I must have made at least 5 or 6 typos or reading errors already tonight. And thank you very much!
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Quoting atmosweather:


No that's correct according to radar. SSE...if it was SSW the middle of her center would be on the coastline.


You're right, I was looking at an old forecast point, not a center fix.

Apologies for any confusion - haven't been getting enough sleep through this.

Really appreciate your posts, Atmos.
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Quoting WatchingThisOne:


That should be about 15 miles SSW of Atlantic City, not SSE.


No that's correct according to radar. SSE...if it was SSW the middle of her center would be on the coastline.
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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.