Ex-Hurricane Florence

[rixxxgolf]

My money is on a CAT2 in the Atlantic, and she'll turn away easily.

We'll see it in 10 days odd as a good rain area.

The previous was an un-educated guess lol.

[Gray-Wolf]

Part of what draws me to Atlantic basin Hurricanes is the sheer weight of techno that can get thrown at them, real time, if they pose a threat to the U.S. Sadly if it doesn't look as though Florence will treat us to that if she continues to follow forcast tracks and we'll then be left watching the remnants get absorbed mid-Atlantic and plotting their course to our shores.............Bah, Humbug.

[kold weather]

Indeed GW and some time al lthat techno still isn't nearly good enough!!!

Just a discussion about the track and possible landfalls up the road, while USA mainland landfall isn't looking likely, the facts are this one is still very worthy of watching.

Models in tight agreement now and I think the re-curve idea is just about sold on me now. Still there are two places that will have to watch Florance very closely. Bermuda and also far E.Canada will have to watch to see how Florance develops. models are in good agreement that at the very least Bermuda may end up in the stronger eastern section of the storm and I'd guess at the very least we are looking at tropical storm force winds. The possible worst case would be Florance as a cat-3/4 going just to the west of Bermuda (something the models ARE progging!) and the eastern eyewlal hitting Bermuda, which would cause some pretty massive damage to the island. This is one situation that will have to be watched closely, esp given that this is an island and there is only one way to escape such a place.

Further north and I feel that Nova Scotia will also have to be on high alert, because as I said on UKWW forum, I feel a 65-75kt hurricane is quite plauseable in that region given I feel a NNE track is likely once past Bermuda's latitude, plus fast foward movement. Then you've also got the fact that its likely to be a big storm and will be travelling over the gulf stream just 12-18hrs before such a landfall which will keep Florance in good shape.

For now there has been no real change in the organisation of Florance, apart from some slight weakening as the convection has flared down. also worth noting there is still no noteable centers of circulation, just several vorticies circulating around the main larger broad circulation. I'd say there probably won't be much of the way of strengthning tonight bar the usual flare-up of convection that usually occurs overnight.

[Brrr]

Belinda -

This is partially the reason why the Atlantic has been slow this year- With El nino assisting the formation of pacific waves, Storms & Eventual Hurricanes there is a rule of thumb to observe- Busy Pacific Quiet Atlantic-

This holds true more often than not...

.....

Best regards

S

Thanks for that Steve, some were saying El Nino was causing sheer, reducing the chances of hurricane production, whilst others were saying it had no effect!.

By the way, is the SAL the same thing that brings up the odd rare day of a red sand dust covering all over our area here in Dublin? I know this event is of Saharan origin.

It certainly amazing all the things that go in to the pot! and the rule of thumb is certainly true to form at the moment.

Are we sure KW/GW it's now heading off from the US coast?...Nova Scotia!... double drat!...

The estimates were certainly off this year for what type of season it was going to be... still there's time yet!.

And I agree that the techno facility is why I'm more interested in this area than any other (.. it makes it far more fun to follow - if that's the right word!)... and I have to admit a vested interest in the Texas area.

Hi John from Dublin - there's also Matty Matt who lives in Portmarnock on this site... normally hanging out in the local weather forecast area !.

Belinda

Edited September 6, 2006 by Brrr

[summer blizzard]

000

WTNT41 KNHC 062034

TCDAT1

TROPICAL STORM FLORENCE DISCUSSION NUMBER 13

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062006

500 PM EDT WED SEP 06 2006

EVEN AS FLORENCE SHOWS SIGNS OF BECOMING BETTER ORGANIZED...THE

CENTER REMAINS MADDENINGLY DIFFICULT TO TRACK. THE WELL-DEFINED

LOW-CLOUD SWIRL HAS BEEN ROTATING NORTHWARD THIS AFTERNOON AROUND A

PRESUMED BUT INVISIBLE OVERALL SYSTEM CENTER TO ITS WEST. AN 18

HOUR AVERAGE GIVES 295/8 FOR THE ADVISORY MOTION. THERE HAS BEEN NO

CHANGE TO THE TRACK FORECAST REASONING...SO I'LL JUST PLAGIARIZE

THIS MORNING'S DISCUSSION. THE KEY SYNOPTIC FEATURE IN THE SHORT

TERM REMAINS THE UPPER LOW CENTERED A FEW HUNDRED MILES NORTHWEST

OF FLORENCE. THIS COULD IMPART MORE OF A NORTHWARD TRACK OVER THE

NEXT DAY OR SO...AS INDICATED BY THE GFDL MODEL...BUT THE REMAINING

GUIDANCE IS TIGHTLY CLUSTERED ON A CONTINUED WEST-NORTHWESTWARD

MOTION OVER THE NEXT THREE DAYS AS FLORENCE MOVES TO THE SOUTH OF

THE MID-LEVEL SUBTROPICAL RIDGE. NEAR THE END OF THE FORECAST

PERIOD...FLORENCE IS EXPECTED TO ROUND THE PERIPHERY OF THE RIDGE

IN ADVANCE OF A DEEP-LAYER TROUGH OVER THE EASTERN UNITED STATES.

MODEL GUIDANCE REMAINS IN EXCELLENT AGREEMENT ON A NORTHWARD TURN

BY DAY 4. THE OFFICIAL FORECAST IS JUST AN UPDATE OF THE PREVIOUS

ADVISORY...AND IS CLOSE TO A CONSENSUS OF THE WELL-CLUSTERED

PRIMARY DYNAMICAL MODELS.

THE MAJOR CHANGE IN ORGANIZATION TODAY IS THAT THE CONVECTION HAS

BEEN GRADUALLY MIGRATING CLOSER TO THE CENTER OF CIRCULATION. OVER

THE PAST COUPLE OF HOURS CONVECTION HAS ALSO BEEN INCREASING OVER

THE NOW-OBSCURED CLOUD SWIRL...AND THIS MAY BE THE BEGINNING OF A

MORE SUBSTANTIAL INTENSIFICATION. AS THE UPPER LOW MOVES

WESTWARD...SHEAR WILL CONTINUE TO DECREASE AND THE ENVIRONMENT

SHOULD BECOME MORE CONDUCIVE FOR DEVELOPMENT. GLOBAL MODELS AGREE

ON DEVELOPING A LARGE ANTICYCLONE OVER FLORENCE IN THREE DAYS OR SO

AND THE OFFICIAL FORECAST FOLLOWS A BLEND OF THE SHIPS AND GFDL

GUIDANCE IN MAKING FLORENCE A MAJOR HURRICANE. TOWARD THE END OF

THE FORECAST PERIOD...GUIDANCE IS ALSO IN GOOD AGREEMENT THAT

FLORENCE...ALREADY A LARGE CYCLONE...WILL GET EVEN LARGER.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/2100Z 19.0N 51.4W 45 KT

12HR VT 07/0600Z 20.0N 53.0W 50 KT

24HR VT 07/1800Z 21.5N 55.5W 60 KT

36HR VT 08/0600Z 22.7N 58.2W 70 KT

48HR VT 08/1800Z 23.7N 60.7W 80 KT

72HR VT 09/1800Z 26.0N 65.0W 95 KT

96HR VT 10/1800Z 29.0N 67.0W 100 KT

120HR VT 11/1800Z 32.5N 67.0W 95 KT

$$

FORECASTER FRANKLIN

[Gray-Wolf]

It's a good job things change as todays 'steering currents' would put Florence on a track across the greater Antilles and into the Gulf. Well the models have been much better than my ramblings so far this season (as ever) so we'd do better stick with them and hope things develop as predicted 'cause the one thing we all seem to agree on is Florence becoming quite big and powerful.

[kold weather]

Florance doesn't look too bad at the moment however there is still major questions about where its center actually is, certainly latest sat imagery doesn't help and we won't have a decent idea till we get the next visables. Convection however is still very strong in the NE quadrant where there are almost certainly 40-45kts winds and there are some cold cloud tops showing convection is still strong there. In terms of the shear, its still there though it does appear to have lessened a little given the slightly more symmetric however there is still some shear evident as you tell be the main deep convection in the NE quadrant and yet has to wrap around completely.

Shear is further forecasted to decrease over the next 24hrs as the upper level low to its west continues to retreat westward which should mean the southerly shear that is over Florence should decrease. When this happens Florance should become far better looking then it is now. It has to be quickly said that Florence is handling the shear extremely well, no doubt that is because its a bulky storm, at least in terms of size its up there with the biggest. Still after shear relaxes Florance should find itslef over very favorable waters with SST's at 29C and some decent heat content, esp over the Gulf stream awaiting it in 168hrs time or so. I see no reason, given it is such a large storm and already got some good depp convection, that this storm cannot become a fiesty hurricane. quite how powerful is in question but certainly category-3 looks more then possible if it does decide to get organised and sort out the central core issues.

How strong Florence will be is going to be very intresting to note because IF it tracks further east then expected then Bermuda will lay right in Florence's path. even if Florence was to take the expected track Bermuda would probably still get hit by high tropical storm force winds from the strong outer bands simply because of the size of the storm. Models are still forecasting the trough to cause enough of a weakness to start to turn it north. intrestingly enough a strong Canada high forms, which according to the models Florence is supposed to tear through it which while it has got good support from pretty much every models is a rather intresting idea esp as if this is the case the jet flow at higher levels must be potent and fast enough to overcome the block, not oten you see that!

Eventually I still think Newfoundland/Nova Soctia will probably hit by Florence though some of the models are just showing it grazing that area, I think still think the models are creating the weakess to turn Florence north too fast.

Edited September 7, 2006 by kold weather

[SnowBear]

Hi folks, am a little out of touch this week tropical wise, but quickly looking through now...

An interesting one Florence is eh?

Current thoughts on track from the models today, alot more agreeable than they were with Ernesto! lol

The models I am watching at the moment for accuracy are, UKMO and AVNO, along with the GFDL, with Ernesto, the GFDL was the first to pick up the northerly route that Ernesto took, the UKMO and AVNO were the models which got a fair degree of accuracy on the track Ernesto took over Cuba.

Both the UKMO and GFDL take Florence on a track which passes by Nova Scotia, and are in line with the NHC thinking.

As Kold said in his post about the models appearing to be showing the track turning north a little too quickly, the AVNO allows a later turn, this is the model to watch for me, as it was the one which picked up the trend some time before the other models of Ernesto over Cuba, getting the track over the eastern part of Cuba, its exit into the Bahamas area, and the almost skimming the north Cuban coast pretty well. Question is, how far west will it be able to track before the turn north. If the AVNO has picked up a trend, and it can track far enough west, the eastern seaboard isnt out of reach, possibly New York/Maine area. A long way off as yet, a day or two more I think to see how Florence behaves first.

Looking at various loops,

http://www.ssd.noaa.gov/goes/flt/t1/loop-jsl.html

http://www.ssd.noaa.gov/goes/flt/t1/loop-bd.html

http://www.ssd.noaa.gov/goes/flt/t1/loop-rb.html

Having said all above, it seems Florence has take a little "jog" northwards maybe, I think the centre looks to be about 22N/52W, which means a crossing of the 20N line earlier than the forecast track at 50W instead of the forecast 56W? Any early northward move now would make any landfall on the eastern seaboard or Canada less likely, the model in the storm track image above shows the UKMO wanting to take Florence more northerly before coming back in line with the rest later on.

Early days as yet!

Recon are possibly looking to start 12 hourly fixes from tomorrow

Edited September 7, 2006 by SnowBear

[summer blizzard]

000

WTNT41 KNHC 070837

TCDAT1

TROPICAL STORM FLORENCE DISCUSSION NUMBER 15

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062006

500 AM EDT THU SEP 07 2006

FRUSTRATION CONTINUES OVERNIGHT TRYING TO LOCATE THE PRIMARY

LOW-LEVEL CIRCULATION OF FLORENCE. A 0345 UTC TRMM OVERPASS AND A

0507 UTC AMSU OVERPASS PROVIDED SOME INDICATIONS OF AN OVERALL

SYSTEM CENTER...BUT ALSO SHOWED AT LEAST ONE WELL-DEFINED LOW-LEVEL

CENTER TO THE SOUTHEAST OF THAT LOCATION. ENHANCED INFRARED

SATELLITE IMAGERY DEPICTS THE APPEARANCE OF FLORENCE VERY SIMILAR

TO 24 HOURS AGO...WITH A SLIGHT CURVED BANDING FEATURE AND WARMER

CLOUD TOPS. THE INITIAL INTENSITY REMAINS AT 45 KT IN AGREEMENT

WITH DVORAK CLASSIFICATIONS FROM BOTH TAFB AND SAB...AS WELL AS A

RECENT AMSU INTENSITY ESTIMATE.

THE INITIAL MOTION IS ESTIMATED AT 300/9. DESPITE THE QUANDARY

IN FINDING THE INITIAL POSITION...THE TRACK MODEL GUIDANCE

CONTINUES TO BE CONSISTENT AND IN VERY GOOD AGREEMENT. CONSEQUENTLY

THE REASONING IN THE FORECAST TRACK REMAINS UNCHANGED. FLORENCE IS

EXPECTED TO CONTINUE TOWARD THE WEST-NORTHWEST FOR THE NEXT 2-3

DAYS WITH SOME INCREASE IN FORWARD SPEED...THEN SLOW A BIT AS THE

CYCLONE TURNS MORE TO THE NORTH AS IT IS STEERED AROUND THE

PERIPHERY OF A STRONG ANTICYCLONE TO THE NORTHEAST. THE OFFICIAL

FORECAST FOLLOWS THE PREVIOUS FORECAST AND DYNAMICAL MODEL

CONSENSUS CLOSELY THROUGH 5 DAYS.

FLORENCE IS EXPECTED TO REMAIN OVER WARM WATERS AND ENCOUNTER LESS

SHEAR IN 24 TO 36 HOURS AS THE UPPER-LEVEL LOW...LOCATED A FEW

HUNDRED MILES WEST OF THE CYCLONE...MOVES WESTWARD AND WEAKENS.

THIS SCENARIO SHOULD ALLOW FLORENCE TO GRADUALLY STRENGTHEN THROUGH

MOST OF THE FORECAST. THE OFFICIAL INTENSITY FORECAST HOLDS

FLORENCE TO JUST UNDER MAJOR HURRICANE STATUS...HOWEVER IT STILL

COULD REACH CATEGORY THREE IN BETWEEN THE FORECAST PERIODS. THIS

FOLLOWS CLOSELY WITH THE GUIDANCE FROM BOTH SHIPS AND THE FSU

SUPERENSEMBLE. ONCE AGAIN...IT IS IMPORTANT TO REMEMBER THAT THERE

IS LIMITED SKILL IN TROPICAL CYCLONE INTENSITY PREDICTION

PARTICULARLY IN THE 3 TO 5 DAY TIME FRAME.

A SHIP REPORT AT 0600 UTC...FROM MSJZ8...REPORTED A 34 KT SUSTAINED

WIND SOUTHEAST OF THE CENTER. THIS REPORT JUSTIFIED EXPANDING THE

WIND RADII OUT TO 250 N MI OVER THE SOUTHEAST QUADRANT.

FORECAST POSITIONS AND MAX WINDS

INITIAL 07/0900Z 20.1N 53.2W 45 KT

12HR VT 07/1800Z 21.1N 54.9W 50 KT

24HR VT 08/0600Z 22.6N 57.7W 55 KT

36HR VT 08/1800Z 24.0N 60.5W 65 KT

48HR VT 09/0600Z 25.0N 63.0W 75 KT

72HR VT 10/0600Z 27.5N 66.0W 90 KT

96HR VT 11/0600Z 30.5N 67.0W 95 KT

120HR VT 12/0600Z 35.0N 66.0W 95 KT

$$

FORECASTER MAINELLI/BEVEN

[kold weather]

Intrestingly the models are still trending eastwards, despite Florence actually moving further west then they expected 48hrs ago. Seems like either the models are picking up on the short-wave trough being stronger then expected and opening the weakness up even faster or they are over-doing the trough and actually the real track will be to the west. Either way it probably won't make much difference to Bermuda as Florence is such a sizeable system that the strong winds wil lbe felt some way out from the center. Looks like this one could well come very close to Bermuda, though on waht side of Bermuda is a decent question!

I meant to put this in my post this morning but didn't get round to it, however I think a good storm to compare florence to would be Fabian from 2003, it may not be as strong as Fabian but in terms of tracks it may not be far off, at least for the next 72-96hrs and its close movement to Bermuda:

http://weather.unisys.com/hurricane/atlant...ABIAN/track.gif

Storm structure is still messy as the storm has still not sorted out it inner core issues and though shear seems to have eased somewhat this messy inner core is really preventing it from getting any stronger then it presently is, coupled to this and the WV imagery is showing some dry air is being injested into the SW quadrant of Florence. Despite this Florence is a large hefty storm and should be able to weather such things where as storms like Chris couldn't.

Intrestingly over the past 2hrs there has been a sizeable convective burst on its western side, something that hasn't happened recently and something keeping a close eye on as the center could well -relocated under that large burst if it can keep growing, given the lower shear it seems we have right now. If I'm right on this one, expect Florence to finally start looking more the part tommorow morning.

Edited September 7, 2006 by kold weather

[Gray-Wolf]

I hope that the 'Dry air' ingestion will allow the western side of the system to start form, I think there is plenty enough moisture to 'ingest' the remnants of the flow from that ULL that has pulled away west. The NW quad of Florence looks (to me) like a breaking crest and this will (I imagine) follow through/displace the 'dry air further away from Florence's SW flank.

I'm still at the mercy of the forcasters with the track. I can still only struggle to see a/the centre at times and am wholly reliant on plots but again I can only discern a more westerly tack than the forcasters too. I hope K.w.'s right and by tomorrow (around now) we can see not only a good structure but also discernible movement!!!

[crimsone]

000

WTNT41 KNHC 072031

TCDAT1

TROPICAL STORM FLORENCE DISCUSSION NUMBER 17

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062006

500 PM EDT THU SEP 07 2006

FLORENCE REMAINS AN UNUSUALLY LARGE...NOW MORE THAN 900 NMI

DIAMETER... NON-CLASSICAL TROPICAL CYCLONE. THE WIND FIELD WAS

EXPANDED AGAIN...ESPECIALLY IN THE NORTHEASTERN QUADRANT...BASED ON

SURROUNDING SHIP AND BUOY REPORTS. THE OUTER CONVECTIVE STRUCTURE

HAS CHANGED LITTLE TODAY...WHEREAS INNER CORE CONVECTION HAS BEGUN

TO DEVELOP OVER AND TO THE WEST OF THE CENTER FOR THE FIRST TIME.

SINCE FLORENCE IS SUCH A LARGE SYSTEM...CONVECTIVE FLUCTUATIONS IN

THE OUTER REGIONS LIKELY WILL HAVE LITTLE EFFECT ON THE WIND SPEEDS

SINCE THE LATTER ARE DRIVEN MORE BY THE SHARP PRESSURE GRADIENT

BETWEEN THE CYCLONE AND THE LARGE HIGH SITUATED TO THE NORTH. NOW

THAT INNER CORE CONVECTION HAS DEVELOPED...STEADY STRENGTHENING IS

FORECAST FOR THE NEXT 96 HOURS WITH SLOW WEAKENING EXPECTED AFTER

THAT DUE TO INCREASING VERTICAL SHEAR AND COOLER WATERS.

THE INITIAL MOTION ESTIMATE IS 300/12. FLORENCE REMAINS ON TRACK SO

THERE IS NO SIGNIFICANT CHANGE TO THE PREVIOUS TRACK FORECAST OR

REASONING. THE GLOBAL MODELS REMAIN TIGHTLY CLUSTERED ON TAKING

FLORENCE WEST-NORTHWESTWARD AROUND THE SOUTHERN PORTION OF THE

SUBTROPICAL RIDGE THROUGH 72 HOURS...AND THEN TURNING THE CYCLONE

NORTHWEST AND NORTHWARD INTO A BREAK IN THE RIDGE THAT IS FORECAST

BY ALL THE MODELS TO DEVELOP IN 72-96 HOURS. THE OFFICIAL FORECAST

TRACK IS CLOSE TO THE PREVIOUS TRACK AND THE NHC MODEL CONSENSUS...

AND BRINGS FLORENCE VERY NEAR BERMUDA IN ABOUT 96 HOURS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 07/2100Z 20.6N 54.9W 45 KT

12HR VT 08/0600Z 21.5N 56.6W 50 KT

24HR VT 08/1800Z 22.8N 59.0W 55 KT

36HR VT 09/0600Z 24.0N 61.3W 65 KT

48HR VT 09/1800Z 25.2N 63.3W 75 KT

72HR VT 10/1800Z 28.1N 65.7W 90 KT

96HR VT 11/1800Z 32.0N 66.0W 95 KT...NEAR BERMUDA

120HR VT 12/1800Z 38.0N 63.5W 90 KT

$$

FORECASTER STEWART

[Gray-Wolf]

Will she ever show consistant signs of development? Now a non-descript ,elongate blob with some banding to the north.Maybe by the time the moisture to the north has wrapped around a centre then she'll look a bit better. Will we have a pretty storm this year?

[kold weather]

Well there was i yesterday hoping that she'd gain some sort of decent look and while it has improved a little overnight its still not enough to really justify upping the winds at all. It's a weird little storm though I did have a feeling this would cause more problems then Ernesto did a couple of days ago, its certainly just as puzzling!

At least it has stil lgot a decent amount of convection near or over the LLC which is an improvement from this time yesterday but its still a rather strange looking system with only few signs of banding.

At a guess I'd say its simply that the inner core is soooo large that any development is very slow to be responded too. Combined with some pretty dry mair still all around Florence and also with it merging with another invest to its SE, which is no doubt causing some dis-organisation in the inner core and so despite lower shear and very decent water temps Florence simply hasn't had the chance to get any stronger.

Track looks nailed on now and a track very close to Bermuda looks likely, best case would be for Bermuda to be on the western side of Florence which probably won't be that strong even if Florence does still get upto hurricane strength. Intensity-wise, this system is quite difficult to forecast simply because it has not played ball at all, I should think that once it sorts out its inner core that it could strengthen pretty readily given the good heat content below it and I'd still call for a cat-2/3 as well by 96hrs but for goodness sake Florence please sort yourself out!!!

Edited September 8, 2006 by kold weather

[Hurricane Debby]

UPDATED: 12:00 am EDT, September 9, 2006

BERMUDA BRACING FOR FLORENCE

Fabian did it in 2003 and it looks like Florence could do it again in 2006. The NHC forecast track takes Florence, forecast to be a hurricane, right over the small Atlantic island. In this case, it won't matter much of the center passes directly over the island or not because the wind field of Florence is so large. In fact, swells generated by the enormous fetch of wind will reach the East Coast of the U.S. over the weekend- they are already being felt across portions of the NW Caribbean. It also looks like Florence is getting better organized and indeed it could become a hurricane fairly soon. The Hurricane Hunters are out there now from what I understand and we will know a lot more about the internal structure of Florence soon. Hopefully people in Bermuda will be ready and Florence won't be anything like Fabian- we shal hope for the best.

We are also watching what was once a suspect area that appeared to be getting absorbed in to the large circulation of Florence. It now appears that it could develop some over the coming days- especially once Florence gets out the way. We will keep an eye on this feature but don't expect much to come from it. I will have more here in the morning.

Courtesy Hurricane Track

[kold weather]

Track idea is exactly the same as the last forecast with Florence forecasted to move NW then turn northwards towards the island of Bermuda before re-curving and starting to become extra-tropical. Bermuda should prepare for a hurricane and hurricane watches will probably be issued for that region later today. Either way Beruda should be ready though there is still a real chance of it heading further west then the NHC currently expect given there is a some models that are about 50 miles further west, which would take Bermuda out of the eyewall if it was right. Either way though Bermuda should be prepared for a hurricane, prehaps a strong one even.

Florence has really improved in strcuture over-night as the shear finally eases and it has finally sorted out its inner core issues that its had for a good few days. The thing that is stopping it from really strengthening fast now is just its sheer size. Anyway recon is in Florence right now and intrestingly has only found top winds of 61kts, which is about 50kts at the surface however what is intresting is that pressure has dropped a fair bit, down to 993mbs now which is getting closer to hurricane status, esp for large storms. So dont be suprised to see the winds respond later today and indeed Florence either getting very close to hurricane status or actually reach it later on today sometime. Still Florence has some decnt conve ction all around it now and is as I hoped, finally looking the part of a decent strengthening storm. As I said before the only real thing pegging Florence back right now is just its size. Still right now it does look quite impressive, given the large convective flare-up and very cold cloud tops indeed in the middle of the system, its not that suprising really that pressure dropped 5mbs in the time it did, not rapid strengthning but certainly I'd expect steady strengthening today into hurricane status.

Edited September 9, 2006 by kold weather

[Paranoid]

000

WTNT31 KNHC 091434

TCPAT1

BULLETIN

TROPICAL STORM FLORENCE ADVISORY NUMBER 24

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062006

1100 AM AST SAT SEP 09 2006

...FLORENCE CONTINUING TO SHOW SIGNS OF GETTING BETTER ORGANIZED...

...TROPICAL STORM WARNING ISSUED FOR BERMUDA...

AT 11 AM AST...1500 UTC...THE GOVERNMENT OF BERMUDA HAS ISSUED A

TROPICAL STORM WARNING FOR BERMUDA. A HURRICANE WATCH AND A

TROPICAL STORM WARNING ARE NOW IN EFFECT FOR BERMUDA. A TROPICAL

STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED

WITHIN THE WARNING AREA WITHIN THE NEXT 24 HOURS. A HURRICANE WATCH

MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA

...GENERALLY WITHIN 36 HOURS. A HURRICANE WARNING MAY BE REQUIRED

LATER TODAY.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE

INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED

BY YOUR LOCAL WEATHER OFFICE.

AT 1100 AM AST...1500Z...THE CENTER OF TROPICAL STORM FLORENCE WAS

LOCATED NEAR LATITUDE 24.7 NORTH...LONGITUDE 63.7 WEST OR ABOUT 530

MILES...850 KM...SOUTH OF BERMUDA.

FLORENCE IS MOVING TOWARD THE NORTHWEST NEAR 13 MPH...20 KM/HR...AND

A GRADUAL TURN TOWARD THE NORTH-NORTHWEST IS EXPECTED DURING THE

NEXT 24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 70 MPH...110 KM/HR...WITH HIGHER

GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS...

AND FLORENCE COULD BECOME A HURRICANE LATER TODAY. AN AIR FORCE

RESERVE RECONNAISSANCE AIRCRAFT WILL PROVIDE A BETTER ESTIMATE OF

THE INTENSITY OF FLORENCE LATER THIS AFTERNOON.

FLORENCE IS A LARGE SYSTEM AND TROPICAL STORM FORCE WINDS EXTEND

OUTWARD UP TO 345 MILES...555 KM FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 992 MB...29.29 INCHES.

STORM SURGE VALUES OF 6 TO 8 FEET WILL BE POSSIBLE ALONG THE COAST

OF BERMUDA AS FLORENCE PASSES NEAR THE ISLAND.

IN ADDITION...LARGE OCEAN SWELLS AND DANGEROUS SURF CONDITIONS...

INCLUDING STRONG RIP CURRENTS...ARE ALREADY AFFECTING BERMUDA...AS

WELL AS THE NORTHERN LEEWARD ISLANDS...THE VIRGIN ISLANDS...PUERTO

RICO...HISPANIOLA. THESE CONDITIONS WILL BEGIN TO AFFECT THE TURKS

AND CAICOS...THE BAHAMAS...AND THE EAST COAST OF THE UNITED STATES

OVER THE NEXT DAY OR TWO. SEE STATEMENTS FROM LOCAL WEATHER

SERVICE OFFICES FOR DETAILS ON COASTAL CONDITIONS.

REPEATING THE 1100 AM AST POSITION...24.7 N...63.7 W. MOVEMENT

TOWARD...NORTHWEST NEAR 13 MPH. MAXIMUM SUSTAINED WINDS...70 MPH.

MINIMUM CENTRAL PRESSURE...992 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE

CENTER AT 200 PM AST FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 500

PM AST.

$$

FORECASTER STEWART

Winds currently at 70mph and pressure at 992mbar. I hope if it continues on its projected path the damage in Bermuda isn't too bad.

[Roger J Smith]

New data will be coming out shortly from the hunter aircraft, but whatever that reveals (probably a minimal cat-1) the more significant factor is that the storm is gradually coming into phase with a very good strengthening environment both in terms of upper level wind pattern (a supporting 573 dm 500-mb low shows up in 48h) and three days of 28-29 C water temps ahead.

Therefore looks rather ominous for Bermuda on Monday, with the eye of potentially cat-3 storm just to the west and moving north, adding gustiness to the strong eastern quadrant of this storm, could see wind gusts to 120 mph and a very high storm surge due to the track.

Later on, current models are indicating a direct hit on southeast Newfoundland, the area known as the Avalon Peninsula where the capital, St Johns, is located. There are certain bays and inlets in this region that are prone to storm surge damage given the right wind directions, both SSW and NNE have associated danger zones as you'll gather if you look at a map of the area. Usually, the Avalon gets 2-4 remnant hurricane encounters a season, most of them tracking more from the SW than this storm, so consequently somewhat less intense since they have to cross colder water. This storm will create a surge of warmer Gulf stream water and could arrive in Newfoundland on Wednesday at cat-1 or even cat-2 intensity, even if it is structurally extratropical -- winds could be gusting to 100 knots, and the offshore Hibernia oilfield may be right in the track of the strongest winds.

Hurricanes have created havoc in Newfoundland in the past, but mostly in the days before reliable warnings. In August 1926 a large loss of life occurred when a hurricane swept through the Newfoundland fishing fleets and harbours, on a similar track to this storm by the way.

Ireland and Scotland may be feeling the winds from extratropical Florence around Friday and Saturday, as it tries to catch up to another deep low in the subarctic jet stream zone.

[kold weather]

Intresting post Roger, i agree about Newfoundland region, I guessed for a 70-75kts hurricane/hybrid extra-tropical system and i agree there could well be strong gusts when it gets there possibly into the cat-2 range if the system is moving fast enough and also being enhanced by Barolinic processes.

In terms of structure, it does look very good indeed however there is an intresting sdtatement that is probably preventing Florcence from being upgraded right now:

HOWEVER...AFOREMENTIONED MICROWAVE DATA SUGGEST THAT THE

MID-LEVEL CIRCULATION IS TILTED 12-18 NMI NORTHWEST OF THE

LOW-LEVEL CENTER AND THAT THERE WAS NO EYE FEATURE PRESENT.

Indeed recon still hasn't found winds that are nearly high enough to warrent an upgrade. Still despite this it does look like a hurricane presently and the sat.estimates all do seem to agree on this being a hurricane and therefore i'd guess it won't be long under the current strengthening trend before the NHC decides to take a dip and upgrade Florence. My guess is that its probably at 65kts right now but its just a guess. The only thing really preventing it right now is some slight shear and also its large bulk will make responding to pressure drops and improvement in structure slow. Still I can't say that i'm not suprised that Florence was upped to 70mph earlier today, mind you not quite as strong as I expected...not quite!

Despite this as Roger said it is about to go over even more favorable waters with some high heat content, but prehaps more importantly is that the movement to the NW/NNW should finally remove it from the shear which is still giving some slight stacking issues at mid-level. There are still some very cold cloud tops despite it being the peak of daytime heating...which indicates that come tommorow morning we could be looking at a decent strengthened hurricane. Pressure is still dropping but winds are slow in responding, depsite this hurricane status is probably not far away for Florence

So expect hurricane watch to come out for Bermuda shortly, how strong it is when it reaches Bermuda is up for question, but I'd guess it would be between 90-100mph given how well its organising our structure.

also in all probablity this will be our best looking system this year and our strongest one this year as well, not that that is saying much mind you!

Edited September 9, 2006 by kold weather

[Dawlish]

Bugger! This one could really upset my spot!

You can never trust these extra tropicals in Autumn. Something for me to learn from, if it spoils my forecast of a settled spell stretching through next weekend.

Paul

[WhiteFox]

Still time for Florence to strengthen, but recent weakening as a result of shear has taken the pressure up to 1000MB and wind speeds down to 65mph. Forecasts still suggesting potential for strengthening to hurricane, but it looks like much above Cat 2 is unlikely (although not impossible!).

Shear is currently coming in from the South-East weakening the outflow. No defniable eye has yet been observed.

Weather centres over here are calling it the "Year of the Shear" due to the amount of storms which have been weakened by wind shear!

[kold weather]

Well the shear is gone now evereyone, better take a look at the images and vis. sat iages are going to be very intresting to see this morning as its looking far better. Since last night Florence pressure has dropped a furthur 12mbs down to 981mbs which is pretty fast. Also prehaps most intrestingly is that Florence has an eyewall according to the very latest obs from recon which means an eye isn't far away.Also worth noting that Florence has a very good outflow, esp on its NW quadrant.

Despite having a pressure down to 981mbs the highest winds so far that have been found is 84kts at flight level which is high enough for an upgrade to 65kts, though given the improvement of the Sat. image I wouldn't even be suprised to see it upped to 70-75kts come next advisory.

This isn't the best of news for people in Bermuda as Florence does seem to be organising pretty rapidly as it moves NW/NNW into the highest area of heat content in this area of the basin and shear has lowered to the point of almost not being a problem. The only good thing is that Florence is still quite a size with an estimated 30N.mile eye so any fairly rapid pressure drop like we are seeing today will take a while to feed into the system. Still depsite this I'd guess Florence could well still hit Bermuda as a cat-2/3, despite only having a fairly short window of strengthening before Bermuda feel the effect of Florence, afterall it is such a large hurricane.

[Mondy]

Pressure down to 978mb

VORTEX DATA MESSAGE

A. 10/07:29:10Z

B. 27 deg 33 min N

065 deg 30 min W

C. 700 mb 2935 m

D. NA kt

E. NA deg nm

F. 034 deg 055 kt

G. 304 deg 069 nm

H. 978 mb

I. 9 C/ 3062 m

J. 17 C/ 3051 m

K. 7 C/ NA

L. OPEN NE, SW

M. E03/50/40

N. 12345/ 7

O. 0.02 / 5 nm

P. AF301 0306A FLORENCE OB 13

MAX FL WIND 84 KT NE QUAD 05:36:20 Z

Bermuda Radar clearly shows the outer bands of Florence approaching.

Harbour Webcam Java, does work!

Sharkoil - Bermuda weather services

Bermuda Weather Services II

Edited September 10, 2006 by Mondy the clumsy

[Gray-Wolf]

Well she does look a lot prettier this a.m. I never worry to much about places like Bermuda as I figure them not too poor to cope!!! (I'm probably misguided). Shame she's on the 'recurve track' that is plotted for her as I figure that means her paying us a visit in the not too distant future. If she does I hope she stays north of the Shetlands as then she may just bring us warmth and not copious amounts of rain!

When I look at the 'steering currents' charts she does seem to be on the edge of the 'Northerly' shifting streams and very close to the ones flowing into the gulf across Cuba......

[Mondy]

Down to 976mb now