Causes of the Russian heat wave and Pakistani floods

By: Dr. Jeff Masters , 2:56 PM GMT on August 13, 2010

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The Great Russian Heat Wave of 2010 is one of the most intense, widespread, and long-lasting heat waves in world history. Only the European heat wave of 2003, which killed 35,000 - 50,000 people, and the incredible North American heat wave of July 1936, which set all-time extreme highest temperature records in fifteen U.S. states, can compare. All of these heat waves were caused by a highly unusual kink in the jet stream that remained locked in place for over a month. The jet stream is an upper-level river of air, between the altitudes of about 30,000 - 40,000 feet (10,000 - 12,000 meters). In July over Europe and Asia, the jet stream has two branches: a strong southern "subtropical" jet that blows across southern Europe, and a weaker "polar" jet that blows across northern Europe. The polar jet stream carries along the extratropical cyclones (lows) that bring the mid-latitudes most of their precipitation. The polar jet stream also acts as the boundary between cold, Arctic air, and warm tropical air. If the polar jet stream shifts to the north of its usual location, areas just to its south will be much hotter and drier than normal. In July 2010, a remarkably strong polar jet stream developed over northern Europe. This jet curved far to the north of Moscow, then plunged southwards towards Pakistan. This allowed hot air to surge northwards over most of European Russia, and prevented rain-bearing low pressure systems from traveling over the region. These rain-bearing low pressure systems passed far to the north of European Russia, then dove unusually far to the south, into northern Pakistan. The heavy rains from these lows combined with Pakistan's usual summer monsoon rains to trigger Pakistan's most devastating floods in history.


Figure 1. Winds of the jet stream at an altitude of 300 millibars (roughly 30,000 feet high). Left: Average July winds from the period 1968 - 1996 show that a two-branch jet stream typically occurs over Europe and Asia--a northern "polar" jet stream, and a more southerly "subtropical" jet stream. Right: the jet stream pattern in July 2010 was highly unusual, with a very strong polar jet looping far to the north of Russia, then diving southwards towards Pakistan. Image credit: NOAA/ESRL.

What caused this unusual jet stream pattern?
The unusual jet stream pattern that led to the 2010 Russian heat wave and Pakistani floods began during the last week of June, and remained locked in place all of July and for the first half of August. Long-lived "blocking" episodes like this are usually caused by unusual sea surface temperature patterns, according to recent research done using climate models. For example, Feudale and Shukla (2010) found that during the summer of 2003, exceptionally high sea surface temperatures of 4°C (7°F) above average over the Mediterranean Sea, combined with unusually warm SSTs in the northern portion of the North Atlantic Ocean near the Arctic, combined to shift the jet stream to the north over Western Europe and create the heat wave of 2003. I expect that the current SST pattern over the ocean regions surrounding Europe played a key role in shifting the jet stream to create the heat wave of 2010. Note that the SST anomaly pattern is quite different this year compared to 2003, which may be why this year's heat wave hit Eastern Europe, and the 2003 heat wave hit Western Europe. Human-caused climate change also may have played a role; using climate models, Stott et al. (2004) found it very likely (>90% chance) that human-caused climate change has at least doubled the risk of severe heat waves like the great 2003 European heat wave.


Figure 2. A comparison of the departure of sea surface temperature (SST) from average just prior the the start of the great European heat waves of 2003 and 2010. Temperatures in the Mediterranean Sea were up to 4°C above average in 2003, which has been implicated as a major cause of the Western European heat wave of 2003. Image credit: NOAA/NESDIS.

References
Feudale, L., and J. Shukla (2010), "Influence of sea surface temperature on the European heat wave of 2003 summer. Part I: an observational study", Climate Dynamics DOI: 10.1007/s00382-010-0788-0

Stott, P.A., Stone, D.A., and M.R. Allen (2004), "Human contribution to the European heatwave of 2003", Nature 432, 610-614 (2 December 2004) | doi:10.1038/nature03089. (Here is a free version of the paper, presented at a conference.)

The World Meteorological Organization (WMO) has posted an analysis of the recent extreme weather events, concluding, "the sequence of current events matches IPCC projections of more frequent and more intense extreme weather events due to global warming."

See also my posts, The Great Russian Heat Wave of 2010: 102°F in Moscow and, Over 15,000 likely dead in Russian heat wave; Asian monsoon floods kill hundreds more.

Moscow sees real relief from the Great Russian Heat Wave of 2010
For the first time in more than a month, temperatures at Moscow's Domodedovo airport failed to exceed 30°C (86°F) today. Clouds and thunderstorms blew into the city this morning, keeping the high temperature down to just 29°C (84°F). This breaks a string of 35 straight days when the temperature reached 30°C. At Moscow's official observing site, the Moscow Observatory, this string was 30 days. Moscow's average high temperature for August 13 is 20°C (68°F), so today's temperatures were still well above normal. However, today's cool-down marks the beginning of the end for Russia's great heat wave. The latest forecast for Moscow calls for high temperatures below 30°C for the coming week, and Moscow may not exceed that threshold for the remainder of summer. Long range forecasts from the ECMWF and GFS models continue to suggest that a series of troughs of low pressure will attack the ridge of high pressure anchored over Russia, bringing cooler temperatures just 5°C (8°F) above average to Russia late next week. By ten days from now, the ECMWF model shows a strong trough of low pressure over Moscow, and a end to the Great Russian Heat Wave of 2010. Moscow still has to concern itself with smoke from the wildfires burning southeast of the city; winds are expected to shift early next week and bring the smoke towards the city again. However, the cooler weather should aid fire-fighting efforts, so the smoke problems should not be as bad as last week's nightmare.


Figure 2. Image from NASA's Aqua satellite of smoke from wildfires burning to the southeast of Moscow yesterday, August 12, 2010. Northerly winds were keeping the smoke from blowing over the city. Image credit: NASA.

The tropics are quiet
The remnants of Tropical Depression Five continue to bring heavy rain to portions of Southeast Louisiana today. Up to five inches of rain has fallen in regions near New Orleans. The GFS model predicts that the remains of TD 5 could move off the coast of Mississippi by the middle of next week and regenerate, but none of the other models is making this forecast. Both the GFS and ECMWF models are predicting that a tropical storm will develop off the coast of Africa by next Friday, August 20.

Donations urgently needed in Pakistan
The devastation wrought by the worst flooding in Pakistan's history requires a huge response by the international community. Wunderblogger Dr. Ricky Rood, author of our Climate Change Blog, has a friend working in Pakistan who underscored the desperate situation there:

This is the worst natural disaster in the history of Pakistan in terms of number of people and area affected. Although not as many people have been killed as in the 2005 earthquake, we have already nearly 900,000 displaced persons thus far just in Khyber Pakhtunkhwa. Crops are destroyed; shops, hotels, and other business have simply been swept away in Swat, which had just this year been cleared of Taliban and was on the way to recovery; and districts closer to Peshawar and parts of Peshawar district are still, or perhaps again after yesterday/today, under water. After the immediate emergency response, it will be years of rebuilding to replace what has been lost and to start to develop again. I know you have the power to control the weather, so if you cold give us a week or two without more rain at least we could keep the helicopters flying and give people a chance to go to their homes, recover what might still be there, set up tents if we can get enough to them, and start to clean up."

She gave the following recommendations for charities that do work in the flood-ravaged zone, and are effective at getting aid to those who need it the most:

Doctors Without Borders

The International Red Cross

MERLIN medical relief charity

The mobile giving service mGive allows one to text the word "SWAT" to 50555. The text will result in a $10 donation to the UN Refugee Agency (UNHCR) Pakistan Flood Relief Effort.

She mentioned that it is better to send money to the organizations doing the relief work than to try to organize shipments of goods.

Jeff Masters

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Quoting robj144:


Ok... where does it mention 219 mph winds?

I am more interested in what piece of equipment measured those winds. Most tools can not measure winds that fast.
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Quoting stormwatcherCI:
LinkHere is a link that tells the story of this legend.

Fasinating. I have never heard of the "gray man". Thank you for saving me the time to look it up. What strange things weather conversations can lead to, lol.
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Quoting beell:


Has to make it back to the coast first. Surface low is about gone. Mid level is weak. If it can hold together back to/near the beach, maybe.
I'm not too bullish either on the intensification, but I'm wondering why considering the conditions set to be present, would it not intensify, and how all the models are out to lunch.

12z PSU e-WALL steering layers suggest that is begin SW motion in about 24 hours. Interestingly enough, the 925mb vort max is just off the Alabama coast.

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1022. robj144
Quoting stormpetrol:
Link


Ok... where does it mention 219 mph winds?
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Wow. Amazing to see THIS in the middle of August.... lol

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I personally think it will ride the coastline and then push off to the east and that is after it continues to weaken. When using the models look at the last 6-12hours first. They ar ento close so then you ahve to adjust the models. Right now I wouldn't use them but hey what do I know?
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1019. flsky
Quoting Patrap:
Video taken by Guerra Family during Hurricane Katrina. Chalmette, LA.

8 miles East of NOLA Downtown.





Patrap, it always breaks my heart to see this video, but thank you for posting it. People will see it and learn.
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Link
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1017. robj144
Quoting BahaHurican:
Just remembered that Hurricane Gustav 2008 now holds the N Hemisphere record for highest hurricane wind... also hit Cuba...


What's going on here tonight with wind speeds? Gustav didn't even reach cat. 5:

Link
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Quoting MiamiHurricanes09:
Why would it not intensify? 31C+ SSTs, favorable/marginal upper level conditions, minimal dry air. You just aren't making sense...even if the models are over doing the intensity, conditions will be a "go" for the intensification of ex-05L.

It had three days out in the open water with no land interaction and it never intensified so why is it hard to believe when only the southern half of the system moves over water that it wont intensify? SSTs are not the only thing that affects the system. TD05 only had 10 kts of shear. Also you assuming upper level conditions are favorable off of the same model that is forecasting to strengthen it. So of course they would have favorable upper level conditions. The question is will it really? Probably not.
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BTW, if u want to put in ur 2 cents on the blog legends, u have 2 more hours 2 make up ur mind and post ur list on my blog... also some interesting posts by others in there.
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1014. beell
Quoting MiamiHurricanes09:
Why would it not intensify? 31C+ SSTs, favorable/marginal upper level conditions, minimal dry air. You just aren't making sense...even if the models are over doing the intensity, conditions will be a "go" for the intensification of ex-05L.


Has to make it back to the coast first. Surface low is about gone. Mid level is weak. If it can hold together back to/near the beach, maybe.
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Quoting BahaHurican:
Just remembered that Hurricane Gustav 2008 now holds the N Hemisphere record for highest hurricane wind... also hit Cuba...
Yep that Dude gave us a blow too I remember the howling from him!
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1011. Patrap
Video taken by Guerra Family during Hurricane Katrina. Chalmette, LA.

8 miles East of NOLA Downtown.




Member Since: July 3, 2005 Posts: 426 Comments: 128636
1010. Ossqss
Quoting HaboobsRsweet:

Actual forecasts and not just models.


It will be crucial as to how far the system drops into the Gulf waters in the next few days. The farther over the water, the stronger, from what I see. Models don't matter now, the observations do. :)

Oops, gotta go :)
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Just remembered that Hurricane Gustav 2008 now holds the N Hemisphere record for highest hurricane wind... also hit Cuba...
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1008. robj144
Quoting charlestonscnanny:
Unbelieveable waves in Cuba from Ike video. It really does make it real to see on video. This is why I try to look at as many videos as I can. I can't really learn about hurricans if I don't understand the damage they can cause.


In the wiki on Ike it mentioned the highest wave under the eyewall was 130 feet! Didn't know that... that's a 10+ story building.
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Quoting robj144:


Trying to read that in one sentence was hard. :)

Are there any links to this? I never heard of that before and that's 49 mph or like 30% more than the recorded peak wind speeds which is an enormous amount when you're considering the wind speeds of a cat. 5. This would been have been huge news at the time and tough to keep silent.

Surprising what a small tiny Island can do to keep secret, when its number one resource is tourism! Enough said, Ever been in a position that you knew something was true , but really couldn't prove it! Well, That is the position I'm in and it depends on who is who here to back me up!
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Quoting HaboobsRsweet:

You would probably need to be in clear air mode to pick up on fires as smoke does not reflect energy back as well as water does with rayleigh scattering. You would not get returns like that with smoke from a fire.

In 99 or 98, can't remember when Daytona and e central Fl had the big fires it picked it up.
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Quoting HaboobsRsweet:

They all were out to lunch on the intensity for TD05 so yes they all could be out to lunch again. Look at the verification of the models today and dont take them for what they are. They are way off on intensity. While I agree the track may be ok it will not be a TC. No way it because a Depression. Look at the real data and not just a math equation trying to forecast the weather.
Why would it not intensify? 31C+ SSTs, favorable/marginal upper level conditions, minimal dry air. You just aren't making sense...even if the models are over doing the intensity, conditions will be a "go" for the intensification of ex-05L.
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Unbelieveable waves in Cuba from Ike video. It really does make it real to see on video. This is why I try to look at as many videos as I can. I can't really learn about hurricans if I don't understand the damage they can cause.
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1003. robj144
Quoting HaboobsRsweet:

You would probably need to be in clear air mode to pick up on fires as smoke does not reflect energy back as well as water does with rayleigh scattering. You would not get returns like that with smoke from a fire.


Just going to mention that.
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1002. robj144
Quoting TampaFLUSA:

I asked bc sometimes fires get picked up on radar and it seems its not moving much...


Drown those pythons! :)
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Quoting TampaFLUSA:

I asked bc sometimes fires get picked up on radar and it seems its not moving much...

You would probably need to be in clear air mode to pick up on fires as smoke does not reflect energy back as well as water does with rayleigh scattering. You would not get returns like that with smoke from a fire.
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1000. robj144
Quoting TampaFLUSA:

Are those fires?


Looks like radar to me.
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Quoting MiamiHurricanes09:
Radar imagery of thunderstorms over the Florida everglades.

I asked bc sometimes fires get picked up on radar and it seems its not moving much...
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Quoting MiamiHurricanes09:
Models always do poorly when forecasting the 200mb level, so it is not surprising that they did not do well in this situation. Now, the ULL is no longer in the picture, so unless the GFS, ECMWF, UKMET, CMC, and NAM are all out to lunch, chances are that ex-05 will be re-emerging into the Gulf of Mexico and turning into a tropical cyclone once more.

They all were out to lunch on the intensity for TD05 so yes they all could be out to lunch again. Look at the verification of the models today and dont take them for what they are. They are way off on intensity. While I agree the track may be ok it will not be a TC. No way it because a Depression. Look at the real data and not just a math equation trying to forecast the weather.
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Quoting TampaFLUSA:

Are those fires?
Radar imagery of thunderstorms over the Florida everglades.
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Quoting stormpetrol:

You're right, I should Have mentioned unofficial, It is widespread knowledge here that the Government of the time actually tried to cover up and underestimated the damage caused by Ivan strictly for political reasons and in the interest tourism , but they were tossed out the following year, what most failed to realise is that PPM that took over were respeonsible for our great recovery and growth after Ivan, they were thrown last year to my dismay and many others with a grain of sense only to put the same person back in power that covered up the devastation of Ivan, not that it means anything to you , just shows what a bright electorate we have here :)


Trying to read that in one sentence was hard. :)

Are there any links to this? I never heard of that before and that's 49 mph or like 30% more than the recorded peak wind speeds which is an enormous amount when you're considering the wind speeds of a cat. 5. This would been have been huge news at the time and tough to keep silent.
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Quoting MiamiHurricanes09:

Are those fires?
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Quoting HaboobsRsweet:

Ok so I think the models are overdoing it again. Remember all the models agreed that 05L was going to be a TS as well but did that pan out? Nope because looking at water vapor the ULL to the NW was pulling all that moisture away not allowing the broad low to tighten up and build. To this point the models have not had the intensity anywhere close. Even over forecasted rainfall rates for today.
Models always do poorly when forecasting the 200mb level, so it is not surprising that they did not do well in this situation. Now, the ULL is no longer in the picture, so unless the GFS, ECMWF, UKMET, CMC, and NAM are all out to lunch, chances are that ex-05 will be re-emerging into the Gulf of Mexico and turning into a tropical cyclone once more.
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The blog is pretty slow tonight.
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I agree Patrap. Katrina was a monstrous beast. She filled the entire GoM and her wind field was huge.
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Quoting HaboobsRsweet:

Nope I agree...I think GFS is overdoing it again.
The GFS is not the only model predicting ex-05L to re-emerge into the Gulf of Mexico along with intensifying it into a tropical cyclone. You can add the ECMWF, UKMET, CMC, NAM, and the NOGAPS keeps it around the coast before shooting it northward.
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Quoting pilotguy1:


Aviation weather center, Intellicast, Plymouth State Weather Center.

Actual forecasts and not just models.
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Quoting robj144:


Is this the link to the 219 mph winds? I looked for that and couldn't find it, but I found this:

"Ivan's strength continued to fluctuate as it moved west on September 11, and the storm attained its highest winds of 170 mph (270 km/h) as it passed within 30 miles (48 km) of Grand Cayman..."

Weren't the highest sustained winds in Camille and Keith with winds of about 190 mph?

You're right, I should Have mentioned unofficial, It is widespread knowledge here that the Government of the time actually tried to cover up and underestimated the damage caused by Ivan strictly for political reasons and in the interest tourism , but they were tossed out the following year, what most failed to realise is that PPM that took over were respeonsible for our great recovery and growth after Ivan, they were thrown last year to my dismay and many others with a grain of sense only to put the same person back in power that covered up the devastation of Ivan, not that it means anything to you , just shows what a bright electorate we have here :)
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Quoting extreme236:


But it's not just the GFS.

Ok so I think the models are overdoing it again. Remember all the models agreed that 05L was going to be a TS as well but did that pan out? Nope because looking at water vapor the ULL to the NW was pulling all that moisture away not allowing the broad low to tighten up and build. To this point the models have not had the intensity anywhere close. Even over forecasted rainfall rates for today.
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Quoting stormpetrol:

I'm curious Have you ever watch Unsolved Mysteries years ago hosted by the late great Robert Stack, about the "Gray Man" It involved Hurricane Hugo in SC some Island I can't remember exactly, Pollys Island it sounded like or something like that , whoever the gray man appeared to their property and home would be spared , well it showed one home in which the gray man had appeared to , all other homes were damaged or destroyed and not even a towel left on the balcony was blown off, weird, Have you or anyone else here ever heard that story?
Interesting. No, I haven't heard of that show and the gray man. It would have been Pauley's Island south of Myrtle Beach. I will definetly look into that. I would love to read about it. Til then, thanks for the tip.
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Quoting HaboobsRsweet:

Nope I agree...I think GFS is overdoing it again.


Its not just the GFS
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One can drive across the Camille Impact Zone in 40 Minutes.

I saw the devastation there in 69 as my Grandparents Lived in Bay St. Louis off of Hwy 90 3.5 Miles from the Beach.

I was 9.5 at the time and saw Man walk on the Moon a Month earlier.

Katrina pushed 7 feet of water across My Grandparents Home and Highway 90...and for 6 miles more inland.

It takes 3 Hours to Drive across her Impact Zone.

1500 plus Lives lost and 240,000 folks were displaced.

The largest US Shift in Population since reconstruction after the Civil War.

Camille was only talked about in Hushed tones for decades. Till August 2005.

And those who saw Both,,would in a moment say there is no Comparison,,period.

And if you saw Coleman Ave,,in Waveland,Miss where a 30ft plus Surge went thru..one can see easily from Pascagoula and east of Mobile Bay to Houma,La. what that Historic storm toll was and remains.

Impact is the determining factor.

Always.

Camille although A powerful cat 5 at Landfall,was a relatively small Hurricane in Size.


To compare one Storm over another isnt like comparing dogs and cars.

.."Calamity Knows no Borders,only men's minds and Maps do....

Katrina Base Map with thumbnails,re-loaded


Member Since: July 3, 2005 Posts: 426 Comments: 128636
Quoting HaboobsRsweet:

Nope I agree...I think GFS is overdoing it again.


But it's not just the GFS.
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981. txjac
All I can say is wow ...this blog has been awesome this evening ...what a pleasure, thank you all so very much
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Quoting pilotguy1:
I see no evidence that TD5 is going to re-appear out in the GOM on any of the charts I am looking at. Anybody see anything to the contrary?

Nope I agree...I think GFS is overdoing it again.
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Quoting pilotguy1:
I see no evidence that TD5 is going to re-appear out in the GOM on any of the charts I am looking at. Anybody see anything to the contrary?


What are you looking at? All Global Models including regional models show not only a return into the Gulf of Mexico but a re-intensification to tropical cyclone status.
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Quoting Babsjohnson:


Heard that the other models are now in agreement with the return of 5 into the GOM


And the redevelopment of it
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Quoting MiamiHurricanes09:
Very impressive outflow channels continuously being depicted by the GFS when ex-05L re-emerges into the Gulf of Mexico.

GFS 200mb Forecast, Day 4:


Heard that the other models are now in agreement with the return of 5 into the GOM
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Quoting BahaHurican:
I'm not sure how I'm going to get Ivan and Camille on there, since they both happened before the blog itself got started.... maybe some kind of honourable mention??
Understood , no problem, both good candidates, just an honarary mention :)
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Quoting stormpetrol:
Link


Is this the link to the 219 mph winds? I looked for that and couldn't find it, but I found this:

"Ivan's strength continued to fluctuate as it moved west on September 11, and the storm attained its highest winds of 170 mph (270 km/h) as it passed within 30 miles (48 km) of Grand Cayman..."

Weren't the highest sustained winds in Camille and Keith with winds of about 190 mph?
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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.