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 WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO



Maybe ;)
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Quoting gulfcoastmom:


Ok, I have been following this conversation and I just had to jump in. As a disaster response coordinator for the military let me explain something. A service member if asked to evacuate can go where ever they want for safety. The 150 mile radius is how far they will get paid their travel entitlement to evacuate. The only exception to this is if the service member is an essential personnel that needs to stay behind and secure the installation. The installation commands will set up a safe haven ( evac area) away from the danger of the storm, and it is usually 150 miles at them most. I hope this helps you to understand a little more. If not please ask.


Thank you. A voice of reason instead of POTUS hate...

Btw, they didn't completely evacuate Hurlburt or Eglin for Opal, Ivan or Dennis, so why would they even considerate for Isaac?

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Quoting sar2401:


Proves what? Did you read the last paragraph?

"Gadian says the theory isn't proven enough to try out on Isaac, pointing out: "Much more research is needed and we are clear that cloud seeding should not be deployed until we are sure there will be no adverse consequences regarding rainfall."

This is one guy in the UK proposing something which hasn't been done and no one knows if it will work. I think your tinfoil hat needs adjustment.

They tried cloud seeding back in the 60's. They gave up on that.
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Quoting Hurricanes101:
922. forecaster1 12:40 AM GMT on August 28, 2012

Exactly, for the last day and half, it has never made sense to me how the forecast models have this this busting through the steering that is in place. In fact the hpc showed their forecast and it had Isaac moving NW right into the trough; that makes no sense




Yes, I do not listen to models or others forecast on these storms just maps and datum.. It keeps my head clear and my mind on the actual conditions.. Many here are married to thier favorite models and do not want to be wrong so they go with the flow.. To each his own! I have been wrong once before. lol
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Quoting wxhatt:
More Recognition about the seeding of Isaac! :

Link


Somehow, I knew chemtrails would show up somewhere in your post. Do you actually believe anything that David Icke says or has written? Even less, some anonymous poster on his website? What can I say.....?
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Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO

Member Since: Posts: Comments:
Quoting hurricanehunter27:
Its an eye. Right over the center. Won't be there in view for long as the overshooting tops will cover it.


So it is an eye......so that means it's strengthening?
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Quoting Tazmanian:



well then take it too other blog
Hey, I had to pull your leg a little bit, taz...

LOL

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995. MahFL
Isaac and his nightly burst of convection.....

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Quoting WeatherfanPR:
I think Isaac has just formed an eye !!!
Quoting washingtonian115:
With the rate Isaac is going I don't think he'll ever be a hurricane.


One after the other, Awesome! LOL
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Quoting Chicklit:


Isaac obviously doesn't take himself seriously enough.
Still hoping he meanders over to Texas and skips NOLA. I cannot imagine dumping all that water in New Orleans even though Ole Miss could use some freshening up. Anyway, I'm not in charge, fortunately, so what will be will be.


far chance. It looks like he has been jogging east of the NOAA track towards Mobile AL
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Quoting CaicosRetiredSailor:


soon...

Looks like a wine sack. good gosh. what a glutton.
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Quoting wxhatt:
More Recognition about the seeding of Isaac! :

Link


Don't click that link unless you want to go to davidicke.com. Reported.
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Quoting TropicalAnalystwx13:

Thanks for showing me the most ridiculous thing I've seen all year.


Though I doubt it, maybe not so ridiculous at all.... Its not the first time that Silver Iodide or other chemicals have been seeded into a hurricane... Since the 60's US had ongoing projects going... Even today China uses it quite often and private companies all over the world...

The thing is that it can go either way... weaken or strengten a system...

Nah... what's been with Isaac all the way has been dry air...
Member Since: August 2, 2010 Posts: 21 Comments: 9651
Quoting TheHurricaneDundee:
yeesh...look at all that grey
Look at the big dry air entrainment channel. I know some of y'all just love a pretty storm and I allow for that, but here in NOLA, that the thing we are all looking at.
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Quoting Ryuujin:


Um... how big is that eye? -.- Or is it one?
Its an eye. Right over the center. Won't be there in view for long as the overshooting tops will cover it.
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Quoting TomballTXPride:

Over water in a shallow continental shelf, thus substantially lower TCHP. That's the main reason storms usually tail off their intensity when they approach the northern Gulf coast. We have seen it too many times. It's either that or an EWRC like Katrina but with Isaac his last 12 hours over water ain't gonna do him any good if he looks like this still.


You act like storms have never strengthened on approach to the Northern Gulf. I can think of one glaring storm, Camille, that rapidly intensified going inland to Mississippi. When upper level conditions are favorable, the water depth is not an issue as long as it doesn't move less than 10mph or so.
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soon...
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Quoting TropicalAnalystwx13:
Well, um...



Um... how big is that eye? -.- Or is it one?
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983. Caner
Quoting HurricaneHunterJoe:
it has had a bit of a further eastward componet for the last 8 hours,unless the NHC center positions are incorrect. will need to be watched .


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Quoting gulfcoastmom:


Ok, I have been following this conversation and I just had to jump in. As a disaster response coordinator for the military let me explain something. A service member if asked to evacuate can go where ever they want for safety. The 150 mile radius is how far they will get paid their travel entitlement to evacuate. The only exception to this is if the service member is an essential personnel that needs to stay behind and secure the installation. The installation commands will set up a safe haven ( evac area) away from the danger of the storm, and it is usually 150 miles at them most. I hope this helps you to understand a little more. If not please ask.


That was my understanding..lol
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Quoting Elena85Vet:


Took in some dry air and disrupted what eye wall he'd been building.


Please read Angela's blog post. Pretty much sums it up.
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Quoting seafarer459:

Commander in chief Pffft. To him, it's just a job perk.
What about family, do they get to go? I'm sorry. As a veteran, I find this asinine. If your 150 miles inland from say, Pensacola. why in God's name, would He want you to drive to the coast?
If I thought Prez Obama was this stupid, I'd be thinkin' what you're thinkin'. Which is why I say something is fishy about this.

OTOH, if you were already 150 miles inland from Elgin, wouldn't you just stay at the base you were on?

This doesn't sound right. I just hope nobody gets hurt because of what seems a rather illogical policy decision.
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Quoting mitthbevnuruodo:


Commercialized would be PAID ads. So would have nothing to do with bias, but everything to do with who will pay to put ads on. Here in the UK, WU's loaded with cheezy ads for '1 trick to look years younger' or cheezy life insurance ads...just saying


Read the site with ads for about 5 years. Then joined, and POOF no ads. $10 was not a lot to pay when they needed the donations. I know folks may feel differently now that they are part of TWC. I now return you to your regularly scheduled mostly weather discussion.
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Quoting gulfcoastmom:
Ok, I am not an expert by no means, but was looking at some maps and radars. Is this thing moving north? Should those of us east of MS be concerned?


If you're on the coast, the bay, the river, creek or another low lying area subject to flooding, you should take this seriously.

If you're inland you'll be fine assuming you have suitable structure.
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Quoting seafarer459:

Commander in chief Pffft. To him, it's just a job perk.
What about family, do they get to go? I'm sorry. As a veteran, I find this asinine. If your 150 miles inland from say, Pensacola. why in God's name, would He want you to drive to the coast?


Ok, I have been following this conversation and I just had to jump in. As a disaster response coordinator for the military let me explain something. A service member if asked to evacuate can go where ever they want for safety. The 150 mile radius is how far they will get paid their travel entitlement to evacuate. The only exception to this is if the service member is an essential personnel that needs to stay behind and secure the installation. The installation commands will set up a safe haven ( evac area) away from the danger of the storm, and it is usually 150 miles at them most. I hope this helps you to understand a little more. If not please ask.
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For those interested in live TV coverage from New Orleans...and who have DirecTV...tune in to channel 349. Thanks to the blogger who posted this!
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97L may become Kirk or Leslie at some point it might be like Gordon it didn`t develop until it was far North.
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Quoting FOREX:


looks like it is going North to me, but many on this blog tell me that it is an illusion. So it probably isn't moving North.
it has had a bit of a further eastward componet for the last 8 hours,unless the NHC center positions are incorrect. will need to be watched .
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Quoting wxhatt:
Isaac is struggling with dry air intrusion or maybe something has been dropped into the NE quadrant?



Here is PROOF! News Article written yesterday hinting about the upcoming project for Isaac!

Link


Proves what? Did you read the last paragraph?

"Gadian says the theory isn't proven enough to try out on Isaac, pointing out: "Much more research is needed and we are clear that cloud seeding should not be deployed until we are sure there will be no adverse consequences regarding rainfall."

This is one guy in the UK proposing something which hasn't been done and no one knows if it will work. I think your tinfoil hat needs adjustment.

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I didn't say he was getting better organized yesterday, but I did say he was wedged and only really had one place to go. That fact still has not changed. ;)
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971. Caner
Quoting trinigal:


I don't think so. This is the only site in which I've noticed these ads. Generally, ads on other sites have to do more with my interests and really overlap from site to site. I don't want to interfere with the storm discussion but I am guessing others who do not pay for the site see all these 'Vote Obama' ads as well?


I have not seen any ads on this sit,e but i have adblock installed.
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I hate to be a party pooper, but I think infrared imagery is playing tricks on your eyes. I believe what you are seeing, which does remsemble an eye, is convection firing over the center, with the remnants of the previous convective burst laying around at much a lower level in the atmosphere. From the current satellite frames the recent convective burst that is superimposed over the older burst makes it appear that an eye is forming. However, when you consider the fact that recon is no longer saying there is an eye, as well as the fact that cloud tops have been warming prior to the burst, as well as all the dry air, it makes sense that this is not an eye forming. We will see in the following recon reports and satellite frames though.
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You all said Isaac was getting better organized yesterday night.14 hours later he's still struggling..
Member Since: August 14, 2010 Posts: 10 Comments: 15716
Looks like an EWRC with a legit eye wall forming. Also seems that some of the dry air in the eastern quad is getting fleshed out. You can see the EWRC/eye wall formation better on the Rainbow Loop Satellite feeds.
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965. Caner
Quoting wxhatt:
Isaac is struggling with dry air intrusion or maybe something has been dropped into the NE quadrant?



Here is PROOF! News Article written yesterday hinting about the upcoming project for Isaac!

Link


Fantastic... The minute amounts of CO2 humans release into the natural levels = bad for climate.

Any unprovable man made warming = bad.

But screwing around with the Earth's climate control system = good.

/rolls eyes...

What *will* these politically funded 'scientists' come up with next?
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Quoting wxhatt:
Isaac is struggling with dry air intrusion or maybe something has been dropped into the NE quadrant?



Here is PROOF! News Article written yesterday hinting about the upcoming project for Isaac!

Link


Read it all before you go blasting off with dangerous rumours. The final paragraph says:

Gadian says the theory isn't proven enough to try out on Isaac, pointing out: "Much more research is needed and we are clear that cloud seeding should not be deployed until we are sure there will be no adverse consequences regarding rainfall."
Member Since: Posts: Comments:


Isaac obviously doesn't take himself seriously enough.
Still hoping he meanders over to Texas and skips NOLA. I cannot imagine dumping all that water in New Orleans even though Ole Miss could use some freshening up. Anyway, I'm not in charge, fortunately, so what will be will be.
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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?


Commercialized would be PAID ads. So would have nothing to do with bias, but everything to do with who will pay to put ads on. Here in the UK, WU's loaded with cheezy ads for '1 trick to look years younger' or cheezy life insurance ads...just saying
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Quoting aislinnpaps:


Well, then the base commander is. My son has no reason to.
Somebody's up to something.

Who knows....

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Well look at this.

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It looks to me like Isaac is off track. Just north of the NOAA track.

Link
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I marvel over the intelligence and knowledge of this blog. I read the comments because I get information faster here. For example earlier there were comments about the storm seemingly being affected by dry air now the weather channel has spoken of it. But I heard it first here! Keep it coming. Gulfport ms.....
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Quoting greene47:


Active duty here...This just not make any sense!..Obviously the conditions don't warrant a mass evac...they have to pay for gas, lodging, per diem...full for adults half for kids, and mileage on the vehicle, so I understand why they won't evac everyone but...neither Hulburt Field nor Eglin AFB really have the facilities to house all military members and their dependents. Literally, they do not..lol I guess stick everyone up in hangers at Duke Field


Some of the shops and other places are bunkers. But I know what you mean, I said the same thing. They even pay for if you put up other military people because of a hurricane. When I evacuated to another son after Rita and knowing how long it would be until electric was restored, he was paid back to house us because we have military ID cards.
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There are some videos of the flooding in Saint Lucie County, FL here: https://www.facebook.com/tiffany34983
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Quoting wxhatt:
Isaac is struggling with dry air intrusion or maybe something has been dropped into the NE quadrant?



Here is PROOF! News Article written yesterday hinting about the upcoming project for Isaac!

Link

Thanks for showing me the most ridiculous thing I've seen all year.
Member Since: July 6, 2010 Posts: 109 Comments: 30266

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About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.