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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Quoting TomballTXPride:

yeah. Folly beach is in the clear. how's that.

Folly Beach has never been in the clear. A constant fog has always enveloped that tiny sand spit.
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853. Caner
I'm in a bit of a fix...

Went out to get my cable that i hook the generator to the house wiring with only to discover it missing...

Haven't used it since Gustav >.<

I had the kitchen re-floored like a year and a half ago, only thing i can figure is one of the workers lifted it for scrap copper then...

Went to Lowes and The Home Depot, both were out of the 30 amp twist lock plug i need... Guess im gonna have to take off work in the morning and hit up the electrical supply houses, hopefully they aren't out or i am screwed.
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Quoting BahaHurican:
aislinn, that doesn't make sense... if the base they are on is not secure, wouldn't they move the people to another, more secure base? Looking at the Google maps, it's hard to believe miltary in Biloxi wouldn't just drive up the road a bit to where they would be N of I-10....

That seems a bit off somehow... :o/


I know, Baha, that's what has me aggravated. This just came about this morning.
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Quoting SouthDadeFish:
Microwave imagery shows Isaac was becoming much better organized:

37 GHz Color:



85 GHz Color:



But then dry air partially disrupted the core:



Yep

It's gonna take a while to get back what he lost

L. NA
M. NA


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Quoting presslord:
Can somebody please give me the nutshell, third grade version of what's happening with Isaac?


It's been trying to intensify all day long, based on pressure...the pressure has fallen a lot all day long, but the eye-wall collapsed again because of dry air.

Ordinarily, based on this pressure, this should already be a 90mph to 95mph sustained storm. Instead it's 70mph.
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847. auburn (Mod)
Quoting trinigal:


Is this why every time I visit the site, I am bombarded with 'Vote Obama' ads? No political bias here, eh?


10 bucks to become a member and no more ads...
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Quoting trinigal:


Is this why every time I visit the site, I am bombarded with 'Vote Obama' ads? No political bias here, eh?


I click on all those Obama ads I see to 1) drain his campaign funds and 2) help Dr Jeff buy a new wardrobe at the same time.
Member Since: May 31, 2007 Posts: 0 Comments: 1210
Bahamian politics?
Trini politics?
or TCI politics?

: )
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Quoting BahaHurican:
aislinn, that doesn't make sense... if the base they are on is not secure, wouldn't they move the people to another, more secure base? Looking at the Google maps, it's hard to believe miltary in Biloxi wouldn't just drive up the road a bit to where they would be N of I-10....

That seems a bit off somehow... :o/


I thought this was at the base commander's discretion?..We were not ordered to evac for the "K" storm, so I really don't see Hurbie or Eglin getting the order for Issac
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Quoting GTcooliebai:
Latest HWRF also shifted east:



Starting to get confused with all of the different charts. Is this Issac or one of those later storms.
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841. FOREX
Quoting Orcasystems:


Is this close to Destin?

about 80 minutes East of Destin.
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Quoting presslord:
Can somebody please give me the nutshell, third grade version of what's happening with Isaac?

Big, big storm getting hurt bad by dry air.
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Quoting trinigal:


Is this why every time I visit the site, I am bombarded with 'Vote Obama' ads? No political bias here, eh?
The Republicans could prolly buy just as many ads if they wanted to. More, actually, since the news people keep talking about how much money the Republicans have.

So are we going to talk politics now, or weather?

{big grin}
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This looks good. For Isaac anyway.

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Quoting presslord:
Can somebody please give me the nutshell, third grade version of what's happening with Isaac?


Member Since: February 11, 2012 Posts: 84 Comments: 7997
ok system is moving between NW and NNW it appears, I really do not think this will landfall in Louisiana
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Quoting HoustonTxGal:


I sure hope it does not become all commercialize now the TWC has it's mitts in it.


It already is commercialized as WU has been selling ads for years. You can pay to stop them of course. Welcome to the 1% Dr Jeff. You deserve it.
Member Since: May 31, 2007 Posts: 0 Comments: 1210
Quoting FOREX:


We eat there all the time. Cool place. Glad you checked it out.


Is this close to Destin?
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Quoting Masquer08er:
Proceeding to hunker down.



Me too! The clouds do look weird.
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Apparently the attempt at El Nino is failing.



It may even swing back to a La Nina at this rate...
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Not a bad shot from PFN...

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Latest HWRF also shifted east:

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Can somebody please give me the nutshell, third grade version of what's happening with Isaac?
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Quoting Masquer08er:
Quoting msphar:
What are the coastal tides for the next 36 hours ??
NOLA to Mobile (Mobeel for you Alabamians)

:::cough cough::: moBEEL ;-)


Channel 5 here in Mobile said a little while ago that high tide was at 10 tomorrow morning.
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There is hardly any precipitation east of the center.
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Quoting aislinnpaps:
Talked to my son earlier. He's currently at home but on alert to having to go into base. He's a disaster lead, so can't evacuate. However today Obama decided military cannot evacuate if they are within 150 miles of a military shelter. If there is a military shelter within that 150 miles, they have to go to it, basically to the closest shelter. Now for places like Hurlburt who are on the Gulf, literally, who cares about storm surge, etc.. Sorry, I'm ranting. I know my son has to stay, but the others who could be safer? Ugh.

So, If I'm 149 miles away, I have to drive to a military shelter? What a crock. Does this guy just pull stuff out of his ??? As far as I know, this has never been policy.
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824. Skyepony (Mod)
Looks like a dropsonde from that hot tower in the NE eyewall.


Level Geo. Height Air Temp. Dew Point Wind Direction Wind Speed
989mb (29.21 inHg) Sea Level (Surface) 27.4°C (81.3°F) 23.8°C (74.8°F) 35° (from the NE) 42 knots (48 mph)
1000mb -99m (-325 ft) This level does not exist in this area of the storm above the surface level.
925mb 589m (1,932 ft) 22.4°C (72.3°F) 20.7°C (69.3°F) 40° (from the NE) 55 knots (63 mph)
850mb 1,325m (4,347 ft) 20.8°C (69.4°F) Approximately 16°C (61°F) 50° (from the NE) 56 knots (64 mph)
700mb 2,982m (9,783 ft) 12.4°C (54.3°F) 8.7°C (47.7°F) 50° (from the NE) 50 knots (58 mph)
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823. FOREX
Quoting Skyepony:


Oh nice..the sunset cam there. People coming out to see the sea.


We eat there all the time. Cool place. Glad you checked it out.
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Quoting odinslightning:
everyone in mobile and along the miss. gulf coast better be prepared to not be traveling for the next 2-3 days since we will get the right front quad and this storm looks back loaded to dump out across us over and over.....regardless of where this lands it's is gonna stretch across the gulf coast to the tip of louisiana into fla panhandle with effects for days.....

im in mobile near tillmans corner....there is a dark omnious look in the sky right now....clouds are moving in different directions on different strata of the atmos...feels like tornado weather big time.....
Proceeding to hunker down.
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Quoting HoustonTxGal:


I sure hope it does not become all commercialize now the TWC has it's mitts in it.


Is this why every time I visit the site, I am bombarded with 'Vote Obama' ads? No political bias here, eh?
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Are some of you really already talking about a storm that does NOT even exist? FML
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Quoting aislinnpaps:
Talked to my son earlier. He's currently at home but on alert to having to go into base. He's a disaster lead, so can't evacuate. However today Obama decided military cannot evacuate if they are within 150 miles of a military shelter. If there is a military shelter within that 150 miles, they have to go to it, basically to the closest shelter. Now for places like Hurlburt who are on the Gulf, literally, who cares about storm surge, etc.. Sorry, I'm ranting. I know my son has to stay, but the others who could be safer? Ugh.
aislinn, that doesn't make sense... if the base they are on is not secure, wouldn't they move the people to another, more secure base? Looking at the Google maps, it's hard to believe miltary in Biloxi wouldn't just drive up the road a bit to where they would be N of I-10....

That seems a bit off somehow... :o/
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Quoting odinslightning:



omg...did not know that...lol

and naaaa i would rather dr masters stay here and al can stay in NYC...lol


Bottom sentence from the WU About Us page. Everything's for sale and this site was TWC's biggest competition online.
Link
Member Since: May 31, 2007 Posts: 0 Comments: 1210
Quoting Hurricanes101:


you laugh but do not truly respond.

Typical troll


LOL!!!
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Ew Al Rocker doing the blogs now?.The first beginnings of TWC take over.By next year this site maybe un recognizable.Hopefully nothing like this.

Link
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Post 802. I meant GFDL
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Quoting StormHype:


TWC bought WU in July. What did you expect? Maybe Dr. Master's stays there, and Al Roker comes here. How you like them apples? lol
The Peacock is strutting
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Quoting cat6band:



LOL!!


you laugh but do not give me a reason as to why

Typical troll
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Microwave imagery shows Isaac was becoming much better organized:

37 GHz Color:



85 GHz Color:



But then dry air partially disrupted the core:

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808. Skyepony (Mod)
Quoting FOREX:


Schooners.com has an awesome view of the Gulf here inPanama city Beach.


Oh nice..the sunset cam there. People coming out to see the sea.
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Quoting Hurricanes101:
Isaac looks to be moving due north right now, still not sold on a Louisiana landfall



LOL!!
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Quoting msphar:
What are the coastal tides for the next 36 hours ??
NOLA to Mobile (Mobeel for you Alabamians)

:::cough cough::: moBEEL ;-)
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Quoting StormHype:


TWC bought WU in July. What did you expect? Maybe Dr. Master's stays there, and Al Roker comes here. How you like them apples? lol


I sure hope it does not become all commercialize now the TWC has it's mitts in it.
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Quoting RTSplayer:
A little trigonometry shows it will pass a few tenths of a degree SW of NOLA's center coordinates using linear extrapolation.


Ah . . . linear extrapolation. Do you mean using the current direction, simply draw a straight line from Isasc to the shore? There should be simpler name for that, rather than "linear extrapolation." I'll think of something. To bad the xtrap is taken.
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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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