Isaac approaching hurricane strength

By: Angela Fritz , 9:14 PM GMT on August 27, 2012

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Isaac is walking the line of hurricane status this afternoon after a hurricane hunter mission investigated the storm and found winds of 80+ mph with the SFMR instrument, which looks down at the surface from the plane and estimates what wind speeds are. This instrument has a notoriously rough time in doing so when there's heavy rain, and since the strongest winds were recorded coinciding with the strongest rain, you can imagine that this region of high wind speed could be suspect. The hurricane hunter mission is still in the storm, so I imagine they will issue a special update if needed. Currently the best estimate of wind speed within the storm is 70 mph. Isaac's pressure has been dropping today as well and is now 981 mb. Isaac is moving northwest at 12 mph--no change since this morning. Satellite loops show that Isaac remains large, though asymmetric, with most of the strong thunderstorm activity on the west and southwest side. Isaac's southeast side continues to struggle with dry air and wind shear, which could help to moderate Isaac's intensity as it approaches the coast.

An oil platform in the northern Gulf of Mexico is reporting sustained winds from the north-northeast at 40 mph this afternoon. A buoy west of Tampa, Florida is recording sustained winds around 30 mph, and platforms south of Louisiana are recording winds from 35-40 mph. The widespread heavy rain of yesterday has lightened up in Florida, but a strong line of thunderstorms in one of Isaac's outer bands is training northward along and offshore of the east coast of Florida, affecting everyone from Miami to Jacksonville.

This afternoon the AP reported that Isaac's death toll in Haiti jumped to 19, which puts Isaac's total death count at 21. It appears most of the deaths in Haiti were due to collapsing structures.


Figure 1. Satellite imagery of Tropical Storm Isaac around 3pm EDT on Monday.

Track forecast:
Models seem to be coming into better agreement today on where Isaac will make landfall, closing in on Louisiana and New Orleans as most likely landfall point. The ECMWF, HWRF, and UKMET all suggest New Orleans as the landfall location. The GFS is only slightly west of that. The GFDL is the farthest west, predicting landfall near the Louisiana-Texas border. Landfall timing remains Tuesday night. Beyond landfall, Isaac is expected to move north toward the Midwest through the rest of this week, however, models are showing that the system will likely slow down around landfall time, prolonging impacts like surge and inland flooding.

Intensity forecast:
The closer Isaac gets to landfall without having formed an eye, the better it is for intensity at landfall. Isaac has strengthened only modestly in the past 24 hours, and is still struggling with a less-than-conducive atmospheric environment. The HWRF remains on the high end of the intensity spectrum, suggesting Isaac will be a weak category 2 upon landfall. Other models suggest it will be a strong category 1, but the difference is splitting hairs. The National Hurricane Center's official forecast is for Isaac to continue strengthening over the next day, reaching category 2 at landfall.


Figure 2. Tide gauge data from St. Petersburg, Florida. The green line shows the storm surge. As Isaac's counterclockwise winds blew offshore this morning, water levels feel two feet at St. Petersburg. The winds switched to onshore this afternoon as the center of Isaac moved more to the northwest, bringing a storm surge of two feet to the city.

Storm surge observations from Isaac
This morning, as Isaac's counter-clockwise winds brought offshore winds to the Tampa/St. Petersburg area, ocean waters fell two feet along the coast. This afternoon, winds have shifted to blow onshore, and a two foot storm surge has been observed at Naples, Fort Meyers, and St. Petersburg on the west coast of Florida. Water levels have also begun to rise along the coast of Louisiana, with a storm surge of 1.5 feet already occurring at Shell Beach on the east side of New Orleans in Lake Borgne.

Angela and Jeff

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1854. JeffM
Now that I think about it, it was tunnels. That guy would not give up on the idea.

Definitely some funny stuff on here through the years.
Member Since: August 19, 2005 Posts: 0 Comments: 143
last few frames of Isaac is showing the NE quadrant filling up and shutting out the dry air... could it be winding itself up?? I think so... maybe... hell, who knows!!! LOL!!!

Track is going right over me, so I'm kinda cool with a strong TS/weak cat1 - i dont want my shingles screwed up lol
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Leslie was not a tropical storm when she had that pressure.
Link
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Quoting moonlightcowboy:



Thanks, Kman! Okay, folks, you just got the 411 on Isaac! That's the deal. If he doesn't have a grip on a system, not too many others will!

Oh, Kman, have any Rolaids? Three sandwiches is enough! ;P

Thanks, man! Stay well, God bless!


Saving the Rolaids for mid September LOL.
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Quoting HopquickSteve:

is there a term for wishcasting the pinhole?
"Pincasting"?


"pincasting" ! Ha - love it!
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1849. 2ifbyC
local southern shows such as.

Swamp People
Sons of Guns
Redneck Pawn Stars
Texas Storage Wars

I must admit.. after many episodes... I still have absolutely no idea :)


Dude, ya need to unplug your TV system!!!
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Water over the seawall, two more hours till the top of the tide. May get a bit soggy tonight in Tampa Bay
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Quoting MississippiWx:
Highest reading yet...

Peak (10s) Flt. Lvl. Wind: 70 knots (~ 80.5 mph)


They keep finding pretty strong winds down to a couple thousand feet and below, if an eyewall develops it's not going to take long at all for those winds to get transported down to the surface.
Member Since: September 24, 2005 Posts: 33 Comments: 9265
Beach - really?


WOW! I can hardly wait for Duck Dynesty to start back!..lol
Member Since: August 3, 2006 Posts: 132 Comments: 20635
Quoting Orcasystems:


Victoria BC :)


OH ok..we can be cool then..lol..
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1844. tkeith
Quoting CosmicEvents:
The ants send you a thank you for remembering. LaDobeLady has been back recently.em>
today as a matter of fact Cosmic :)
Member Since: November 1, 2004 Posts: 25 Comments: 8924
Quoting RTSplayer:
Linear extrapolation says the storm will pass 29 miles due west of NOLA, putting them directly under the right front quadrant of whatever eye wall development there may be.

A few hours later, I should be in the same case. I intend to document it all with my digital camera.



Oh, by the way, there is an enormous lunar halo out tonight. It's the largest I've ever seen.


I'll look at my window!
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Quoting JeffM:
Here is something for all of us that were here posting during Katrina 7 YEARS ago!! It's the blog from Katrina.

Link
Wow I can't beleive I was one of those Bloggers back then and got the Track right as it moved off FL.... I also cannot beleive it has been 7 years ago. Some of the Old Names back then LOL.... LOL

Taco :o)
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Me too! I read Tubes and was so confused!
Quoting cjnew:


I thought they were TUNNELS! :D
Member Since: July 10, 2005 Posts: 157 Comments: 29384
Anyone has a gfs screen shot?
OOz obvious tho
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1839. will40
Quoting cjnew:


I thought they were TUNNELS! :D


yup Tunnels
Member Since: September 19, 2005 Posts: 2 Comments: 4138
Quoting greene47:


What part of Canada Orca?..Surely not the part that sent down all the water down the mouse/souris river that flooded my current city of residence last year..lol


Victoria BC :)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting kmanislander:


Open a cold one and make a sandwich !.

NW to just South of landfall is still my position. I like the NHC track with a slight adjustment to the right. The plains high has pushed East and strengthened a bit which will increase the block to the NW. We may see more of a NNW motion near landfall IMO.

As for intensity Cat 1 looks more and more likely absent a significant deepening near the coast. The TCHP levels do not favour that and the inability of Isaac to get it together this afternoon suggests that it is running out of time to do much on the intensity front.



Thanks, Kman! Okay, folks, you just got the 411 on Isaac! That's the deal. If he doesn't have a grip on a system, not too many others will!

Oh, Kman, have any Rolaids? Three sandwiches is enough! ;P

Thanks, man! Stay well, God bless!
Member Since: July 9, 2006 Posts: 184 Comments: 29608
Quoting DFWjc:


How much deeper are the Levees now? Are the gates to block more water coming into the Lake?


Hi all,

I've been a long time lurker and have always appreciated this site for its content. It really is my go to site for tropical weather.

The reason I wanted to write was to address what I feel are some common misconceptions. Am I an expert? No. But, being a lifelong resident of NOLA, I've seen some pretty ridiculous engineering ideas for combating flooding, particularly in Orleans Parish.

To be brief, Orleans Parish allows the lake to meander its way deep into the city at multiple locations with pumping stations at the termini of "outflow canals." These canals hold water at the same level as the lake and have historically been lined with small levees - the Army COE/Orleans Parish modified these levees with walls that were driven down on top of them. (I remember driving by the newly constructed walls and asking my wife if they were simply decorative since they had no buttressing, and thus, no obvious sign of being a retention wall).

Jefferson Parish, on the other hand, is situated exactly the same way as Orleans Parish with Lake Pontchartrain on its north side. Jefferson Parish does not allow the lake to intrude into its limits - it has pumping stations at the lake, which serve as damns/dikes (so to speak), and pump water that is collected in a network of canals throughout the Parish. There are no levees along these canals within the Parish nor along the canals that lead directly to the pumping stations.

The large levees, which most think of when the term is used, did not fail during Katrina. Yes, there was overtopping in locations, but the levees by large DID NOT FAIL. The flood walls protecting inland waterways connected directly to the lake did!! These flood walls were obviously not designed to hold back high water levels to even untrained eyes.

Orleans Parish has installed "temporary" pumps analogous to the locations of the pumping stations in Jefferson Parish. Yet, the stupidity persists in Orleans which relies on "outflow canals" to carry water that is pumped from stations miles inland.

We have perfect examples of how to protect ourselves using the Jefferson Parish model vs. how not to do it using the Orleans Parish system.

Don't allow the water in side the city limits in the first place!!!

Remember, Katrina's devastation was the result of flood wall failure (NOT levee failure!!) which is evidenced by Jefferson's relatively successful outcome post-Katrina - despite Jefferson Parish turning their pumps off during the storm!!

I certainly do not intend to be preachy - I simply want to clarify for those who want to know the difference, since many are completely unaware of the 2 systems sitting side by side with very very different approaches and successes/failures.

Thanks for your patience,

NOLARocks
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1835. cjnew
Quoting Scotth:


Yes! The tubes that would bring cold water up from the deep!...and destroy any cane that came along. WOW! Great memory!


I thought they were TUNNELS! :D
Member Since: July 22, 2005 Posts: 84 Comments: 2779
I am southern as they come, and I must admit I have never watched any of these show or, to be honest, have I ever heard of them????
Seriously?
Redneck Pawn Stars? (I had to read that second word twice).
Quoting Orcasystems:


Hey now be nice... I have spent the last few years studying my southern friends. Trying to see what makes them tick.. so I can try and fit in.

I have religiously watched local southern shows such as.

Swamp People
Sons of Guns
Redneck Pawn Stars
Texas Storage Wars

I must admit.. after many episodes... I still have absolutely no idea :)
Member Since: July 10, 2005 Posts: 157 Comments: 29384
Quoting CallInBatonRouge:


I was here for Katrina, too. This blog was my sanity. It was a miracle to me that so many talents aligned to pre-warn so many people. Even without the ants, this blog called the devastation days before the NHC. It was actually difficult to get non-bloggers to listen but the certainty and evidence presented here made it possible to convince them. Forever grateful.
The ants send you a thank you for remembering. LaDobeLady has been back recently.
Member Since: August 3, 2005 Posts: 10 Comments: 5560
Quoting Orcasystems:


Hey now be nice... I have spent the last few years studying my southern friends. Trying to see what makes them tick.. so I can try and fit in.

I have religiously watched local southern shows such as.

Swamp People
Sons of Guns
Redneck Pawn Stars
Texas Storage Wars

I must admit.. after many episodes... I still have absolutely no idea :)


What part of Canada Orca?..Surely not the part that sent down all the water down the mouse/souris river that flooded my current city of residence last year..lol
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1831. isuxn2
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1830. Scotth
Quoting JeffM:


NOOOOOO!!!! haha The Tubes!!


Yes! The tubes that would bring cold water up from the deep!...and destroy any cane that came along. WOW! Great memory!
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Quoting BlxMS:


Think I joined that night too....I'm 57 and have to admit....seven years ago right now, I was as afraid as I had ever been...and experienced nothing like it since..


Spooky how it's 7 years on the nose. The destruction I saw will stay with me the rest of my life. The one that sent fear to the very marrow of my bones was Rita. And, even surviving intact, driving around coffins floating in the streets still makes my insides weak. There is more that I don't want to remember, but it was my uncle and cousin who saw it and not I.

Brrrr.... I will remember Isaac, however he turns out, for the flashbacks.
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Quoting moonlightcowboy:



Atmos, my answer would be this to the dilemma, and a question. First the question. When a dropsonde is dropped into the eye is pressure measured at the sfc or the mid-levels, or all along the way? If it's at the sfc, then Isaac's llc has been really intense today, more so than at any other time I've noticed according to vorticity charts and observations.

The MLC has been the dominant, broad circ throughout his life, and the smaller llc, trying as it may now, is having an awfully tough time trying to spin that broad mid-level circulation.

May be a bad question, but it's one I've never considered before now. TIA, friend.


I believe a dropsonde measures wind, temperature, dew point and other thermodynamic profiles at all the significant standard pressure levels (850 mb, 700 mb ect.), including any isobaric levels for winds to generate such things as the mean wind in the lowest 150 meters and such, and then measures the barometric pressure at the surface as it falls to the ground.

You're spot on about the intense low level spin today, it was clear this morning that he had tightened his surface circulation enough to be able to generate stronger winds close to the center. But that dry air has inhibited his mid level energy from being transported down into the lower levels and into the center of the storm.
Member Since: September 24, 2005 Posts: 33 Comments: 9265
Quoting Miamigal:
Folks! LOOOONG time lurker before I even joined. I really don't care when you all bicker but I really hate when a voice is silenced because it doesn't agree with the majority. trust me I geared a lot of my preps on Levi,'s thought process. Taz also put up a lot of info as well as Largo and Grotho.


my point is......can't we all just get along?!?!

Seriously different opinions and back up is why it helps a lot of us that don't know as much as you guys and makes us research. Right now I am very very afraid for my disabled father in law in Nola and trying to make decisions on his behalf, place yourselves in my shoes.. Trying my best to make the impossible decision with a cantercous stubborn family member who is no many miles away I can't get to.

That being said I am glad for all of you, you all are a god send in the sea of misinformation.





My heart goes out to you. If Isaac were to go to Texas I would be in your shoes. Terrible feeling.
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TKeith,

Three days ago we all thought this was going to be right on my doorstep...
Hopefully you don't get too much from this.
And like I said, it aint over til the fat lady sings.
I'm almost afraid to go to bed! LOL As soon as my eyes close Isaac will rear his ugly side!

Vanw - you referring to Bonnie?

1794. vanwx 11:02 PM CDT on August 27, 2012 +0
Quoting cjnew:
Foxx the dry air has really made it not bad here. we barely got any rain. waiting to see if that stays through tomorrow.

Does anyone remember when Dr. Masters blog was lucky to break 50 comments? ha. who knew.
now he's on TWC.


1992
Member Since: July 10, 2005 Posts: 157 Comments: 29384
Quoting JeffM:


NOOOOOO!!!! haha The Tubes!!


AMEN!
Member Since: August 3, 2006 Posts: 132 Comments: 20635
Good Night
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1823. Scotth
Quoting will40:


oh yea him and that huge butt lol


He was a rather large fella! lol
Member Since: Posts: Comments:
Quoting tkeith:
canadians...jeesh :)


Hey now be nice... I have spent the last few years studying my southern friends. Trying to see what makes them tick.. so I can try and fit in.

I have religiously watched local southern shows such as.

Swamp People
Sons of Guns
Redneck Pawn Stars
Texas Storage Wars

I must admit.. after many episodes... I still have absolutely no idea :)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting taco2me61:
Don't get me wrong but "We Did Try" thats for sure but they would not listen.... and a lot of people lost the Lives during that storm....

Taco :o)


Made my go/no go decision based on the sat data you could get on the site, not on bloggers
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1820. IMA
Quoting Orcasystems:
Cue the shower curtains... jesting.. please don't.


Too late! I didn't see this until after :)
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Quoting canehater1:


Yeah I just looked at it ..Beautiful...


Can't see that one, too cloudy now, but saw the most unusual thing I've ever seen probably in the sky - there was a large, rainbow halo around the sun this afternoon! Was absolutely beautiful, amazing!
Member Since: July 9, 2006 Posts: 184 Comments: 29608
Quoting Scotth:
In case anyone is wondering what happened to Lefty, he is in Ohio. But do you remember when he went to OBX with killdevilhillsmax? Stormjunkie has a pic of him that day!

LOL I do remember that.
Member Since: August 28, 2005 Posts: 0 Comments: 153
Quoting IMA:
Awwww, so good to see so many old, uhm, I mean "familiar" faces :) Where's JFV, though? heehee I couldn't resist!


Since everyone seems to be reminiscing - I've been a paying member here for nearly 10 years. Can't remember the first time I logged in...used to post as WxDelMarVa, but changed everything earlier this year after finally moving to my long time "vacation spot" and renewing my membership. I was more of a follower of winter storms, and saw more than my fair share up north.

That was then:



This is now:



Member Since: March 9, 2012 Posts: 0 Comments: 149
1816. tkeith
Quoting silverstripes:
More old timer trivia:

Who was the poster who would say "Hey Killer" every time Adrian would post something?

Not sure why I remember this but I do. HA.

squawk...
Member Since: November 1, 2004 Posts: 25 Comments: 8924
Loooooong-time lurker here! I think this is my first post lol. Been following for years. I have to ask, what did Taz say to get so many upset in here. I can't find it.
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GFS moved east. Per TWC.
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1813. JeffM
Quoting snotly:
if you really want to talk nostalgia we need to discuss TUBES!


NOOOOOO!!!! haha The Tubes!!
Member Since: August 19, 2005 Posts: 0 Comments: 143
IMA - ROFL!
Member Since: August 3, 2006 Posts: 132 Comments: 20635
1811. JeffM
Here is something for all of us that were here posting during Katrina 7 YEARS ago!! It's the blog from Katrina.

Link
Member Since: August 19, 2005 Posts: 0 Comments: 143
Quoting GPTGUY:
They just did a story and interviewed cyclone oz on the local tv station here in biloxi


well, at least 2 WU members got TV time during Isaac!..lol
Member Since: August 3, 2006 Posts: 132 Comments: 20635
Ally - that was the last I heard...
Quoting AllyBama:


wasn't he like 16, had his own website and was already interning at the NHC or something like that? I need to google..
Member Since: July 10, 2005 Posts: 157 Comments: 29384
1808. will40
Quoting Scotth:
In case anyone is wondering what happened to Lefty, he is in Ohio. But do you remember when he went to OBX with killdevilhillsmax? Stormjunkie has a pic of him that day!


oh yea him and that huge butt lol
Member Since: September 19, 2005 Posts: 2 Comments: 4138
1807. IMA
Oz can be seen on crazymother.tv I believe he and his brother are both chasing Isaac.

Orca!!! Great to "see" you!! Yeah, I should've just posted this (can't find the older one):
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Bonnie
Quoting vanwx:


1992
Member Since: July 10, 2005 Posts: 157 Comments: 29384
Evening folks! Caught some swell this evening on Pensacola Beach. Good to see some familiar handles here! I still can't shake that old "what will we wake up to" feeling! Hope this storm passes through without much more intensification.
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1804. snotly
if you really want to talk nostalgia we need to discuss TUBES!
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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.

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