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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1054. HCW
Quoting sar2401:


How much you wanna bet? :)


That line has been money and the NHC follows it. $10 :)
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1053. airmet3
Quoting Caner:


Simple question.

Does the earth use tropical cyclones to distribute heat from the equator to the poles and thus regulate its climate?

Yes, no?


Yes. Mother Nature has a remarkable ability to take care of herself.
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1052. FOREX
Quoting WeatherfanPR:


A


All of the above.
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Quoting keithneese:


Good evening Ally. Nervous night here in Mobile.
Hello Ally
Member Since: August 16, 2007 Posts: 0 Comments: 397
1050. Bielle
Quoting Caner:


Just curious, other than being a sort of fruit loop kook site, what is wrong with davidicke.com?

Doesn't appear to be obscene or anything?

And it is a weather related, (albeit insane), thread about someone claiming to have proof they seeded the storm clouds...

Kooky, yes... worthy of reporting someone over per the threads rules? I dont see it.


Perhaps you enjoy "fruit loop kook sites" that promote dangerous weather theories. My concern was that anyone might be directed there from here (which is generally considered to be a scientific and sane site) and take that site seriously because of the connection. Please understand, as nutty as that place seems to you and me, there are people who believe, totally. So, to me. that link is much worse than most spam. (And kook sites frequently have nasty tracking and/or other malware that one might drag back inadvertently.)
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On a positive note, the central/northern regions of Georgia should be getting some rains that will help the extreme drought conditions. NHC forecasting 6 1/2 inches for the Atlanta area.

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Very light rain falling here near Tillman's Corner in Mobile now.
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Quoting BahaHurican:
Thanks for this... I have no experience with the military and how it works in this respect, so this really clarified what seemed like a rather illogical policy to me.

Great! :)
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80,000 still without power in sfl from Isaac. Lots of standing water.
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People have been mentioning a stalling of Isaac, what would cause that at this point? I am not good at reading maps of fronts and troughs, can someone tell me what the influences are upon Isaac now and in the near future?
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1044. sar2401
Quoting HCW:
TVCN shifted East target LA/MS line expect the cone to shift east by 4AM


How much you wanna bet? :)
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Quoting SrChiefFan1:


Eglin kept a security force and disaster response team on location for Ivan and Dennis. I worked with both through emergency services on both events...


aside from the skeleton crew at least..I thought that was understood..lol..my point being,..the new "policy" made NO sense..lol..must be some sort of misunderstanding
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I'm the only brave here LOL come on it's just a poll !
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In short Cancer, the answer to your question is yes. Trop Cyclones are heat transports that distribute excess stored latent heat from the oceans and then distributes that energy poleward.
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Quoting sunlinepr:


Someone please post an animated Gif proving it....
lol, or was that serious?
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Quoting greene47:


Actually Eglin evacuated for Ivan and Dennis...we were 12 hours from the order for Katrina as well...I agree why on earth would they mass evac for Issac..lol..


Eglin kept a security force and disaster response team on location for Ivan and Dennis. I worked with both through emergency services on both events...
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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.
Thanks for this... I have no experience with the military and how it works in this respect, so this really clarified what seemed like a rather illogical policy to me.

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1036. Caner
Quoting ScottLincoln:


As much as you may want them to be, those two situations are not the same. One is weather, the other is climate. One has a mountain of research behind it, the other has been flimsy conjecture and tough to prove for decades. One has substantial amounts of ongoing research, the other is funded substantially less and is not widely accepted.
As an intelligent person, I'd assume you can figure out which is which.


Simple question.

Does the earth use tropical cyclones to distribute heat from the equator to the poles and thus regulate its climate?

Yes, no?
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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?

You know your on a lib site right. In the old days it didn't matter and that was four years ago
Edit 3.75 yrs if if you want to get techy
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1034. HCW
TVCN shifted East target LA/MS line expect the cone to shift east by 4AM
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@ 1009 its going to be poorly defined seeing how it has just developed. That being said they are no longer mentioning it being open to the north.
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1032. Walnut
Quoting Chicklit:
This storm is obese.
And according to prognostications, a slow mover.
So make preps for keeping the water at bay.
Generators with bilge pumps may help, depending on the size of your area.
Fill up those sandbags now.
This will be a huge water event.
Couldn't agree more. Winds will not be the issue. The speed of the storm overall and somewhat the trajectory is the story. Huge amounts of rain if this puppy stalls or crawls ashore tomorrow. NOLA's pumps can only do so much. It could be like pouring water from a full-on garden hose into a bowl while simultaneously sipping it out through a straw.
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I gotta say for an hour or so this afternoon he was organizing and scaring me a little. The dry air makes me feel better... maybe the storm won't be terribly destructive. Whether La or Mississippi we are still a little jumpy since Katrina. My husband was teasing me for rooting for the storm. When he asked me how he was looking I said "bad.". He says a normal person would have said "good" for weaker. I told him I wasn't rooting for the storm, I was just assessing his overall health. I guess I lurk here too much to be normal. Lol
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Meanwhile, my son and his family are in South Korea expecting Bolaven. He thinks they're prepared.
It should be a CAT 1 at landfall.
And the 28th is his 28th birthday.
Lot goin on...sigh
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Quoting hurricanehunter27:
Well yes and no. IF the eye wall is able to maintain itself then yes. Otherwise it will give way to dry air and fall apart.


I see. Thanks for responding.
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Quoting mobilebayal:




C. Scared to say for fear of bashing



LOL, don't worry about that !
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Quoting SrChiefFan1:


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?



Actually Eglin evacuated for Ivan and Dennis...we were 12 hours from the order for Katrina as well...I agree why on earth would they mass evac for Issac..lol..
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Quoting WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO



Someone please post an animated Gif proving it....
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1024. airmet3
Quoting WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO


Negative, though it is trying mightly
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Quoting Tazmanian:
so where are my dry air caster


and eye caster tonight
Looks as though Issac is now starting to blow up
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Quoting Tazmanian:
so where are my dry air caster


and eye caster tonight

Don't forget the RI casters
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1021. Caner
Quoting Bielle:


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


Just curious, other than being a sort of fruit loop kook site, what is wrong with davidicke.com?

Doesn't appear to be obscene or anything?

And it is a weather related, (albeit insane), thread about someone claiming to have proof they seeded the storm clouds...

Kooky, yes... worthy of reporting someone over per the threads rules? I dont see it.
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eye has formed. I am convinced by looking at various sats that it isn't a dry slot. Don't be surprised. NOAA forecasted a hurricane at 11 PM or there about so he is right on schedule. Here is another view of the eye.

Link
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Quoting Tazmanian:
so where are my dry air caster


and eye caster tonight


Dry air caster: JMasters: from today's post.... But he has repeated it in the last 3 posts...

"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".
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If you have directv tune to channel 325 or 349 for local New Orleans news.
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Quoting mobilebayal:




C. Scared to say for fear of bashing


hahaha
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Quoting mobilebayal:


So it is an eye......so that means it's strengthening?
Well yes and no. IF the eye wall is able to maintain itself then yes. Otherwise it will give way to dry air and fall apart.
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This storm is obese.
And according to prognostications, a slow mover.
So make preps for keeping the water at bay.
Generators with bilge pumps may help, depending on the size of your area.
Fill up those sandbags now.
This will be a huge water event.
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Quoting WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO





C. Scared to say for fear of bashing
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1013. Ryuujin
Quoting WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO

Possibly? Perhaps?
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Quoting gusgelpi:


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.


I was just saying about what ads there are as someone thought they put on politically biased ones...not that I was complaining about ads in general. But for me, any given month an extra £6 is pushing it just to not have ads on a weather page TBH. Very poor am I LOL
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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


Ya... it's just google ads... not reflective of Wunderground. Where I live it is constantly popping up ads of a senate race. They have a lot of money to spend.
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Quoting WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO



A
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Again, sorry to be a party pooper, from 4 minutes ago:

Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 28th day of the month at 00:31Z
Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 28
Observation Number: 27
A. Time of Center Fix: 27th day of the month at 23:54:23Z
B. Center Fix Coordinates: 2647'N 8627'W (26.7833N 86.45W)
B. Center Fix Location: 257 miles (413 km) to the S (170) from Pensacola, FL, USA.
C. Minimum Height at Standard Level: 2,981m (9,780ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 53kts (~ 61.0mph)
E. Location of the Estimated Maximum Surface Wind: 90 nautical miles (104 statute miles) to the WSW (258) of center fix
F. Maximum Flight Level Wind Inbound: From 325 at 60kts (From the NW at ~ 69.0mph)
G. Location of Maximum Flight Level Wind Inbound: 110 nautical miles (127 statute miles) to the W (265) of center fix
H. Minimum Sea Level Pressure: 983mb (29.03 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 12C (54F) at a pressure alt. of 3,060m (10,039ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 15C (59F) at a pressure alt. of 3,032m (9,948ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 11C (52F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Poorly Defined
M. Eye Shape: Not Available

N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 700mb
O. Fix Determined By / Fix Level (Undecoded): 1 / 1 nm
Remarks Section - Remarks That Were Decoded...
Maximum Flight Level Wind: 70kts (~ 80.6mph) in the southeast quadrant at 22:34:49Z
Maximum Flight Level Wind Outbound: 63kts (~ 72.5mph) in the east quadrant at 0:00:53Z
Remarks Section - Additional Remarks...
SLP EXTRAP FROM 10K FT
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1008. syn627
.
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Quoting Caner:


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?


As much as you may want them to be, those two situations are not the same. One is weather, the other is climate. One has a mountain of research behind it, the other has been flimsy conjecture and tough to prove for decades. One has substantial amounts of ongoing research, the other is funded substantially less and is not widely accepted.
As an intelligent person, I'd assume you can figure out which is which.
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so where are my dry air caster


and eye caster tonight
Member Since: May 21, 2006 Posts: 5091 Comments: 115247
Ah. Is it the phase of Hurricane formation where we start posting "science" articles from 100% tabloid newspapers in order to prove why the storm isn't doing what we think it should be doing?

Cool.

Personally, I think it's all Prince Harry's fault. He didn't keep what happens in Vegas in Vegas. Due to uncontrolled global exposure to crown jewels all that overwhelming dry cheeky British humor has affected Sir Isaac's NE quadrant.
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Quoting WeatherfanPR:
Quick Poll

Does Isaac just developed an Eye ?


A. YES
B. NO



Maybe ;)
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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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