Hurricane Dean

[kold weather]

Dean is looking very good this morning, got a relaly impressive structure that screams hurricane and it has a really good inflow present feeding up moisture from the ITCZ, it certainly looks like a hurricane this morning. high resolution IR is now showing an eye plus eyewall has formed over the last few hours which a classic sign of the system getting stronger.Given the fanning I saw late last night it seems pretty clear an upper anticyclone is forming over the top of it and if thats the case then this system could very easily rapidly deepen over the next 24-36hrs into a major hurricane like Ivan did at the same longitude and the NHc are going to upgrade in the next advisory with 65kts...tohugh I'd be more inclined to go upto 70-75kts based on the Sat.presentation, its really getting well organised.

Ssytems like this tends to deepen very rapidly once they look like this and Ivan looked very similar before bombing down to cat-3. Given the amtopsheric condtions look pretty good right now heat content suggests that major hurricane is possible presently though probably the lower end. A small system (like Ivan was at this point before it fattened out) will have no problem using the heat content to its max with a small eye semeingly forming it may well undergo rapid intensifcation. Later in the Caribbean after crossing the Leeward Islands as a cat-2/3 I can see easily a very powerful hurricane and like Stev has said te central/western Caribbean can support cat-4/5 no problems...it wouldn't surprise me al lthat much if it ended up in the top 10 strongest hurricanes ever if it goes over the highest heat content though its small size may limit its pressure to 920mbs or so if it uses the heat content like it could...bar the loop current the W.Caribbean is the best place for systems to rapidly develop. Track should take it over very similar water to Allan and Gilbert.

In terms of track, well the models are now in pretty good agreement about the general trend of continuing Dean pretty much a little northof west for the enxt 5 days and indeed the longer range models keep it in the same direction until it makes its second landflal in Mexico. Foward speed is pretty impressive and with nothing to slow it down it could well be the case that Dean is only 4-5 days away from a Yucatan hit. The first hit is expected tomorrow in the Lesser Antilles. The models are then indicating a track very close to Jamacia though it may just skim to the south. needless to say the last landfall there was a certain hurricane Gilbert.

I suspect it may end up heading just to the south of the island putting them in the northern quadrant of the system. depending on its size the effects of course may vary.

Beyond even that and a Yucatan hit is looking more and more likely. Exactly where will depend on the exacts of the synoptic set-up and thats something the models may not have a good grip on right now however the only thing that will likely save them from a very powerful hurricane would be the EWRC and thats always something that is hard to forecast in advance tohugh most likely place for such a thing is the E/Central Caribbean as the heat cotnent takes it another gear once you get into the west Caribbean. The models are currently thinking that the system should stay to the south of Texas, but S.Texas should still be on alert just in case, still till for the models to shift their ideas.

So, we are looking at a hurricane this morning, possibly a major as soon as 24hrs IMO, then steadystrengthening till the W.Caribbean where it could bomb into a cat-4/5. This baby needs to be watched for sure and is likely to be the strongest system since Wilma in 05. Lets see what Dean...soon to be hurricane Dean can do.

[tcc]

Hmmmm, not looking good for my holiday to the Yucatan in 3 weeks time! Looks like even if Dean misses or bypasses the Yucatan, there's other tropical waves that could scupper my plans!

[kold weather]

I have to admit the latest track from the NHC does rather suggest your holiday tcc could be in trouble:

Also now offical...we have our first hurricane of the year. Hurricane Dean with system started at 65kts. NHC expecting cat-4 before Yucatan hit but every chance it'll be in the 150mph+ plus category in the w.Caribbean, could be looking at a monster providing the upper trough doesn't dive down too much, not looking that way tohugh thats why the HWRF weakens the system in the Caribbean on the 0z run.

SHIPS takes it upto 113kts on its 0z run, would be rounded upto a category-4 if that was true.

Edited August 16, 2007 by kold weather

[Iceberg]

Welcome Hurricane Dean, please be gentle though !.

Dean really took the eye creation is a giant leap, small tight eye now formed and clearly visable.

For a well formed eye like this we can assume sub 985mb pressure and winds of 70Kt so fairly rapid strengtening is underway.

Very good outflow and inflow is evident as you mention KW.

He has started to grow as well (another sign that the inportant outflow is occuring).

Can't wait for the recon.

Edited August 16, 2007 by Iceberg

[mezzacyclone]

In relation to Weather Undergrounds prog for Yucatan peninsula (thnx KW!),

can anyone remember which cat5 hit their around 10 or more years ago and caused chaos?

Very entertaining how all of a sudden we can be viewing a potential monster after such a quiet build-up.

[Blackie]

Very entertaining how all of a sudden we can be viewing a potential monster after such a quiet build-up.

I don't think the people in Dean's projected path would see it as entertaining...

[johnholmes]

quite so

[Iceberg]

The eye is now starting to enlarge, with total structural banding around the eye to keep it safe rapid pressure drops are likely occuring.

Maybe down to 970 by now.

[tcc]

There's a Dean in our office, so I've been giving him stick saying he's ruining my holiday plans!

Not looking good is it, oh well I'll have to check with the hotel next week to see how much damage it's sustained. (Assuming the path forecasted turns out to be correct).

Not liking the idea of further tropical waves either!

[mezzacyclone]

I don't think the people in Dean's projected path would see it as entertaining...

I did not Quote the people in Dean's path?, I commented from MY point of view because its what I feel it is - Entertaining

'Entertainment' is my view of this entire thread? If i am convening the Politically Correct standards once again

then feel free to comment further but it is not my opinions that start the risk of swaying threads from their topic titles!

'Entertainment' - I will refrain from using this word from now on before i whip up another Spanish Inquisition!

Entertainment: the act of entertaining; agreeable occupation for the mind; diversion;

amusement, something affording pleasure, diversion, or amusement, esp. a performance of some kind

What an impact and what un-necessary responses a thoroughly unexamined and failure of thorough and meticulous scrutiny to one word of choice brings to our threads?

I suggest to not waste time commenting on my brief notes but either applaude 'KW' and 'Icebergs', amongst others, contributions or post your own technical and/or graphical info?

Lets all jog on fella's

[Roo]

In case it hasn't been posted before this site is great for keeping up to date with what is actually going on out there...

http://stormcarib.com/

My friends on Nevis are getting the board and nails in, just in case: I do hope it won't be a bad one.

[Iceberg]

A nice clear pic of Dean, with the antilles in the background, Interesting to note how large this system is.

The clouded sunken eye is visable, hopefully before the end of today it will clear out.

sorry wrong pic

Edited August 16, 2007 by Iceberg

[kold weather]

Yep the eye is forming right now, not really well defined right now on visible but IR does show its certainly an eye with a noteable warmer area where the new eye is presently. Expect the eye to clear quite quickly over the next 12hrs as it heads into ever increasing heat content. It should also be noted that it is has a tiny eye at the moment and while it has to become better established it is developing quite fast right now. While its outflow is showing growth, its inner core is very tight it appears which explains the small eye.

NHC have upped the winds to 80mph which is to be expected given its increasingly good looks on Satellite. 11.45UTC IR showed a weak eyewall forming on the SW side with a weak eye just starting to form. This is a worrying trend for the Lesser Antilles which could wlel see a high end cat-2/low end 3 hit them with full force, as noted earlier its al lthat different to the way Ivan looked before it becme a major hurricane. I'd be preparing right now if I was on the islands on the southern half of the Leeward island chain, Dominica, Martinique and also Guadeloupe all need to be prepared for a major hurricane, if they don't I fear there will be a big mess.

By the way the 06z GFDL is a big change from the 0z run, it brings it througu the Caribbean then up into the gulf of Mexico going through the Yucatan straits before heading NW towards Louisiana.

Its probably an outlier but the models may be starting to adjust further north again after heading to ofar west, that does tend to happen with such hurricanes that have upper highs to the north, they can be overdone. the 12z runs will be interesting.

Edited August 16, 2007 by kold weather

[Cookie]

stunning images

[kold weather]

Dvorak estimates trending closer to a cat-2 now:

16/1145 UTC 13.5N 53.2W T4.5/4.5 DEAN

that estimates roughly equates to 77kts and 979mbs in pressure, already stronger then the latest advisory suggests. Eye is starting to really beocme evident, there really is no mistaking the eye now on the images, looking more impressive, will almost certainly be a decent cat-2 in the next 12-18hrs if it keeps this level of organisation up:

Accuweather also going for a cat-4 landflal in NE yucatan, for what its worth the models and the offical guidence is slowly pulling mback north, not a lot but every model that shifts that bit further north is making a Texas hit more possible as well as being bad news for tcc...unless it gets so far north it compeltely clears the Yucatan, though thats highly unlikely right now.

Edited August 16, 2007 by kold weather

[Iceberg]

Worth showing that GFDL taking upto and beyond a CAT 5. Truely a frightful prospect.

Edited August 16, 2007 by Iceberg

[Cookie]

Dvarok estimates trending closer to a cat-2 now:

how big do you think it will get?

[Iceberg]

Agree KW a 4.5 is anywhere between 77Kt and 90Kt A CAT 2 is getting close.

[kold weather]

How big it gets is a question that is hard right now to answer, at present its inner core of high winds is rather small and the eye is small however given the expected strength in the Caribbean its gonig to be likely to go through at least one eyewall replacement cycles and so when that happens usually the pressure gradient slackens and the small hurricane becomes slightly fatter in terms of its wind size. Despite that i don't see this system become ultra-bloated like some hurricane shave beocme, tohugh its outflow wil lcotinue to grow as it strengthens.

The new models are running at 75kts with 982mbs as a pressure. In truth I think its probably closer to 85kts at the moment and I suspect once recon goes in their for the first time they'll find winds above waht the current etimates are, Dvorak estimates willcontinue to rise if the improvement in presenation continues...

At least we aen't having any forecasting drama like we had with Ernesto last year, just as soon a sit becoame a hurricane bang and it was weakening back to a TS after it was expected to strengthen.

Looking at it it appears to be deepening a good faster then was expected, could have a first peak as a cat-4 in the E.Caribbean as early as tomorrow eveing, then its in the lap of the gods as to when the eyewall has its first collapse.

Edited August 16, 2007 by kold weather

[crimsone]

Not a bad first hurricane of the season... the last time I saw anything strengthen this fast was back in 2005, somewhere near the end of the name list. Not that I think it'll be comparable in the end, but the tight eye and rapid intensification is a welcome reminder (at least, while it's not over land!)

Recon apparently scheduled for 1800z (and then again 6 hours later... so, 7pm BST and 1am BST)... It'll be interesting when the vortex message comes in.

I remember last year somebody posted up plots of recon's path over the storm and where they were currently... I''d love to know how that was done and where the data came from, but that's a matter for PM's or a different thread perhaps.

Edited August 16, 2007 by crimsone

[tcc]

I'll be hoping it does end up on a more northern track. To be honest even if it's a 100 miles north of Cancun, that won't as bad as the wind will be coming from the west from over the land towards the coast, so "hopefully" this will mean less damage!

Interesting developments ahead I feel

[Iceberg]

Raised to 80Kt in the latest advisory, (which is quite a jump )

Winds are really stretching out from the centre as well, which does not bode well.

MAXIMUM SUSTAINED WINDS ARE NEAR 90 MPH...150 KM/HR...WITH HIGHER

GUSTS. DEAN IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON

SCALE. STRONGER WINDS...ESPECIALLY IN GUSTS...ARE LIKELY OVER

ELEVATED TERRAIN. ADDITIONAL STRENGTHENING IS FORECAST DURING THE

NEXT 24 HOURS. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT WILL

INVESTIGATE DEAN THIS AFTERNOON.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 30 MILES...45 KM...FROM

THE CENTER. DATA FROM NOAA BUOY 41010 INDICATES THAT TROPICAL STORM

FORCE WINDS EXTEND OUTWARD UP TO 105 MILES...165 KM...FROM THE

CENTER.

[crimsone]

@tcc... Hopefully it will be OK for you... perhaps a fair point of comparison would be the last storm to really have a go at the yutacan peninsula, which was Wilma that stalled there for over a day as a cat 5 and really lashed the place. There was a lot of damage, but the situation was fairly extreme in hurricane terms... and even then a lot was left standing (standing with broken windows, and damaged roofs, but still standing!)... http://www.hurricane-wilma.net/cancun_hote...orts/index.html

There is at least a chance that so long as the landfall isn't directly over where you're staying, that your plans may be merely disrupted a rather than cancelled. If this one were to hit Cancun, it almost certainly won't be laboring over the place for 30 hours, and that part of mexico very much relies on tourism and so won't want to be non-operational for long if it can be helped.

There's a long time left to go yet, and so plenty of time for the track to change too.

Edited August 16, 2007 by crimsone

[kold weather]

Ah your talking about Hurricane Wilma crimsone...not sure we can quite compare this to that as that was one of the fastest deepening system ever.

However there are a few systems that look quite similar to Dean around the same region. Ivan was quite a bit further south then Dean BUT it was about the same strength at this longitude. Recon went in and found marginal cat-3 winds, after the previous forecast had called for current winds of 80kts, needless to say it was quite surprising how fast it had developed.

Allen is another system which is very similar to Dean in a lot of ways, aobut as strong at the same longitude and only 1 degree further south as well heading about 280 degrees, or a little north of west. allen went on from becoming a 80kt cat-1 then hit the windward Islands as a 115kt category-4. The residents of Martinique, St.Lucia and Dominica will all be praying that the same doesn't occur to Dean. I think the Allen idea may be a little extreme but the system is organising quite neatly right now and its still easy to see Dean being a boderline cat-2/3 hurricane by the time it smashes into the islands. By the way both systems mentioned went on to be top-10 deepest systems ever.

By the way its worth noting that Dean is now upto 80kts, or in other words 90mph and just below the category-2 range, its increased in strength a lot over thelast 9hrs, gone from a 75mph hurricane to a borderline cat-2 90mph hurricane, given this sort of strengthening its hard to imagine Dean being a cat-3 hitting the Lesser Antilles...

Amazingly Martinique still have not inssue a hurricane warning keeping it as a watc despite this island being at the highest risk of being directly struck by Dean and at the strength I expect this could be sadly extremely dangerous for them..een the NHC takes Dean to just below category-3 status by the time it hits the Islands.

(ps, hopefully they use recon every 6hrs from now on in, by the way crimsone while strong Wilma was weakening by the time it came onland, it abut 145mph I believe.)

Edited August 16, 2007 by kold weather

[Iceberg]

Indeed KW, I see no reason to suspect that Dean is already a CAT 2 and could become a CAT 3 tonight.

Visual sat shows a storm still with a tight eye and stengthening. I'd expect two main outflow paths to become established in the next 12 hours, with the eye growing to around 10-15miles.