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Posted
  • Location: Liphook
  • Location: Liphook

    Well its only May but we already have got a slightly intresting set-up developing. The models have come into agreement for low pressure system to develop in the wes tof the Atlantic, some models taking it down to about 998mbs as well. Now at this time of year it usally is the case that anything such development will be cold cored...however the intrest arrises with the fact the the tropical models are suggesting it MAY start to become warm cored in about 72hrs as it deepens further which is a very intresting event because it could mean a hybrid, maybe a subtropical system could form.

    Anyway right now a low has started to devlop about 400 miles to the east of the carolinas though it is a weak system. The LP is progged to strengthen though as the HP to its north al;so develops leading to stronger winds developing. The main issue is not so much the formation of a LP but exactly what type of LP will it be. Right now its certainly cold cored however the models are progging it to slowly drift SW as a strong high pressure develops to its north shunting it SW. What this does is send it towards the juicy gulf stream waters which is now warm enough in May to support pure tropical development. At the same time shear is progged to ease down for a couple of days which gives a window for some tropical development. The unkowns are whether the SST's are warm enough yetand whether the ide aof lower shear is a right one. Still its intresting, the NAM model for example produces a hurricane by 84hrs, though the model is always known for over-doing warm cored systems and its rarely got it right, at least the strength of the system, but here is it anyway:

    post-1211-1178395830_thumb.png

    Most models do develop the low in one form or the other, tropical or not and its expected to give some rain to those places that haven't seen that much in the SE of the states and the system is expected to give sustained winds of between 35-45mph, so in truth whethe rit goes tropical or not may not make that much difference in the end but its still very intresting and couple, if some of the more aggressive models are right lead to a system to watch and watch for a invest maybe...

    Also while I'm here it may just be worth watching the south Caribbean sea, the GFS for example has been producing a weak LP (no more then Td strength IF IF IF anything does form) down there for a while now and shear is progged to very light with more then warm enough SST's, so we have two areas to watch over the next week, quite a lot for May!

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    Posted
  • Location: London, UK
  • Location: London, UK

    Aye, time is about up. Conditions look reasonable, so it certainly merits a bit of attention even at this early stage.

    Let the games begin I say, I am hopeful this will indeed be the somewhat early kick off storm for this season.

    Calrissian: standing by for Andrea

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    Posted
  • Location: Taunton, Somerset
  • Weather Preferences: Snow, thunder, strong winds. HATE:stagnant weather patterns
  • Location: Taunton, Somerset

    I hope something happens that we can all monitor. April was a very quiet month worldwide for tropical storms, I think it has been a whole month since one was last active.

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    Posted
  • Location: Haverhill Suffolk UK
  • Weather Preferences: Thunderstorms, Squall Lines, Storm Force Winds & Extreme Weather!
  • Location: Haverhill Suffolk UK
    I hope something happens that we can all monitor. April was a very quiet month worldwide for tropical storms, I think it has been a whole month since one was last active.

    Hi Somerset, lets hope so. April was very quiet month. Kolds post is interesting. (Copied below)

    Well its only May but we already have got a slightly intresting set-up developing. The models have come into agreement for low pressure system to develop in the wes tof the Atlantic, some models taking it down to about 998mbs as well. Now at this time of year it usally is the case that anything such development will be cold cored...however the intrest arrises with the fact the the tropical models are suggesting it MAY start to become warm cored in about 72hrs as it deepens further which is a very intresting event because it could mean a hybrid, maybe a subtropical system could form.

    If we were to get something subtropical along with very dry ground, then flash flooding could be a problem - especially where's there's prolonged and heavy precipitation.

    Interesting times.

    Mammatus :wallbash:

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    Posted
  • Location: Taunton, Somerset
  • Weather Preferences: Snow, thunder, strong winds. HATE:stagnant weather patterns
  • Location: Taunton, Somerset

    Indeed, interesting times. Slightly off topic as it's not regarding this year, but can anyone confirm for me that the extremley early storm of March 6th 1908 was entirely tropical. Or was it sub-tropical? What caused this incredibly rare storm?

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    Posted
  • Location: Liphook
  • Location: Liphook

    Models still suggesting LP development and the TC genesis guidence also suggests that it will be a shallow warm cored system before it eventually is dragged inland thanks to the developing HP to its north sliding eastwards. Most models are suggesting a hybrid system at weak TS strength heading westwards towards the dry Se states so flooding could be a huge issue, even if it ends up as a bog standard cold cored LP as the models are progging a lot of rain indeed, some of the more aggressive models get upto 6-8 inches of rainfall over 6hrs.

    The NAM is still going for a hurricane however as I said last night time the model is usually way too agressive in developing these systems. The other models do go for some sort of intresting development but at a much slower rate. Indeed even the NHC maps now show a closed low in 48hrs and with the system heading towards warmer waters near the gulf stream there where its got its best shot.

    SS- without any obs I really can't say but I doub tit'd be purely tropical, I'd suggest some sort of hybrid, sub-tropical system is possible.

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    Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

    Any update on this?????

    Does anybody have a link to the chart which shows the maximum potential energy available in the Carribean, if i have confused anybody, i mean the one which showed that southern Jamica had the highest potential energy available???

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    Posted
  • Location: Liphook
  • Location: Liphook

    Its looking very intresting right now, low pressure has now fully closed off at 1008mbs and has a impresasively tight gradient, winds upto hurricane force in gustsd over the gulf stream where the higher lapse rates are present and the system is very well developed with a huge amount of energy to work with.

    Right now it is purely Barolinic wit hthe front still obviously attached to the low making it a very large system indeed with the northern side bei ng helped by the powerful high tightening the pressure gradient. however intrestingly over the past few hours there has been shallow convection developing clsoer to he ccenter, esp on the western side closer to the warm gulf stream which could well be a sign of things to come. right now the waters are a little on the cool side for tropical development which is why the convection is really not getting stronger and is why the low looks a little like a naked swirl.

    However the really intresting part of this is the rather unusual set-up for the time of year with a the huge high to its north meaning rather then going out to sea like normal the low pressur ewill be dragged WSW towards the gulf stream. This is when it will really have to be watched. It does look good right now however for now its being propped up in terms of its strength by the large area of positive voricity being forced to rush eastwards with the jet through the gap between the cut-off low and the large high block to its north.

    Its from 24-48hrs time that its fate wil lbe sealed either way IMO. It's do or die there. If it does dies into a naked swirl then its probably likely going to stay as a extra-tropical cyclone. However if convection can fire up near the center like its doing now, then despite the cool sea tmeps convection should stil lbe able top get going, esp over the gulf stream. There is a lot of dry air around it which could limit the systems chance sof becoming tropical, but if convection can fire on a greater basis then presently then we may just get a named cyclone from this system. Right now satelite estimates do suggest that it could become a sub-tropical storm but whether or not it'll look nearly so good once the low seperates from the impressive forcing. intrestingly we may know the answer as early as tommorow morning, given the process may already be occuring...

    Whatever happens its heading SW, the NHC latest maps suggest that the system will eventually head into Florida and the models suggest it wil lbe a big rainmaker on its northern side, with little on the southern sides, given thats where the best forcing is its not suprising really. As for winds, well they are progged to decrease even if the system does go tropical because right the gusts have been getting upto 70kts thanks to the tight gradient.

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    Posted
  • Location: Barnet, North London
  • Location: Barnet, North London

    Hi Kold,

    yes, things are starting to brew and this system certainly gives some encouragement! I noticed a couple of storms formed in a similar location last summer (rather than drifting across the Caribbean Sea.

    Storm Floater 4 is up and running on the NHC satellite page, and shows the circulation well, even if it's not closed.

    smich

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    Posted
  • Location: Liphook
  • Location: Liphook

    Hi smich, it has got a closed circulation, indeed its got a central pressure below 1000mbs which would pretty much assure that the system would go right to sub/tropical storm status if it does go barotropic, indee dits pressur eis down to 998mbs.

    Anyway BIG news regarding this system ,it has since been upgraded to Invest 90L, the first of the upcoming season, central pressure 998mbs and winds of 50kts. It probably has another 24hrs over water before it heads inland towards Florida. Right now it does look rather sub-tropical I have to admit. Convection has continued to pop up near the center of the low and has if anythign nicreased as predicited last night over the gulf stream. It still hasn't got much in the way of really deep convection as the sea temps are only marginakl but it does look sub-tropical I have to admit. Given the invest has 50kts winds it would be upgraded to Andrea IF it got the go ahead.

    Right now it kind of looks like one of those early season hybrids, however its to be noted that it is now or neever as probably in about 12-18hrs it'll start to suck in drier air from the coast, and given how dry the SE states has been it could well cause the systme problems if it doe sgo sub-tropical or not. Satelite estimates are still suggesting its strong enough to be upgraded. It's very tight though with the gulf stream waters being mightly marginal at this time of year.

    The key thing that may just swing it in the way of not being upgraded is while ther eis convection ther eis none at all in the center of the circulation, in such a marginal set-up though only the folks at NHC can make the final call and the one thing that is truely against it is time, because ither way it is filling and the graident is slackening and Florida is getting closer now as well. Its a good thing for them though, it should help to relieve many parts from the drought they've been suffering, which has already been started by the strong thunderstorms over the weekend.

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    Posted
  • Location: Barnet, North London
  • Location: Barnet, North London

    Hi kold, I thought closed circulation was when the convection was more extensive and unbroken, or maybe it's just the fact that the system is spinning around itself, but I'll have bow to your much more superior knowledge on that!

    The LP still looks very impressive, not sure if it will be upgraded now though, perhaps it will depend on how much longer it will remain over the water.

    smich

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    Posted
  • Location: Warwick and Hull
  • Location: Warwick and Hull

    0.o wasn't expect a storm so soon. I was expecting not to have a storm until late june or early july. Maybe we might see a lot of storms this season, but hopefully not as damaging as 2005.

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    Posted
  • Location: Liphook
  • Location: Liphook

    Why does it have to do it today when I've got no time, I'll make a breif post by my standards!

    very happy with my call before that it could devlop int oa sub-tropical storm over the gulf stream. current winds at 45mph and so its still moreof a rainmaker then wind maker. System was upgraded after the recon found a small warm core at lower levels, in truth its more of a hybrid then subtropical but alas the guolf stream has poppped convection up enough for aupgrade. Ironic that its moving out of the gulf stream now towards colder waters. However given its a hybrid I'm not sure if that will have much of an impact on the strength. A slow track SW towards Florida nowis present but its very slow and there won't be much of a change in the strength either. In truth it'll probably slowly weaken over the next 36hrs till landflall but winds aren't the issue ,as i said before its the rain which for such a slow moving depression will likely be the main issue, flash floooding is possible given how dry the area is.

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    Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

    Looks pretty enough if a little loose, I suppose it'll give us a chance to get our sites etc. sorted before the start of the main event.

    I only spotted this from the MetO globe sat image and I thought Nah, can't be, but it was!

    Hi! to you all by the way, lets have a clean season, no biting or punching below the belt, when the bell rings come out storming.......

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    Posted
  • Location: Shoeburyness, Essex - 6.2m asl
  • Location: Shoeburyness, Essex - 6.2m asl

    Andrea is going to make it very interesting for golfers taking part in The Players' Championship, which starts tomorrow and goes on until Sunday. It is at Ponta Vedra, near Jacksonville, which would appear to be right in the path of the storm. I just hope Tiger and co have packed their wet weather gear. And if the winds are strong, their big golf umbrellas might not be easy to keep up either.

    Will there be much lightning associated with it? That will play havoc with the golf. Any sign of CG strikes in the area and they stop play immediately. I have played several times in Florida and other states when the klaxon sounds - and you don't hang around!

    Annoying that Sky no longer have the PGA golf events. I don't mind missing most of the tour on TV, but The Players is a tournament I love watching - if only to see the pros made to look human when they hit their balls into the water on the 17th (I guess there will be more than ever this week thanks to the wind). And I don't want to sign up with Setanta on Virgin Media just to watch four days of golf. :whistling:

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    Posted
  • Location: New Zealand
  • Location: New Zealand

    There are currently thunderstorms consolidating on the center (as one might expect) according to the NHC advisory discussion, so assuming that they don't die out before the system reaches land, and provided that the system reaches land at the location of the tournament, there may be a prettygood chance of a storm stopping play.

    Of course, playing Pro golf in a monsoon isn't a usual thing, and so regardless of how stormy the system is, if it makes landfall near the tournament, the chances are it will be stopped anyway (as mentioned by others already, it may well produce enough rain to cause flash flooding on the dry, dry ground - so, not really golfing weather). Not that I have that much of an interest in golf personally.

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    Posted
  • Location: Larbert
  • Location: Larbert

    http://wtvj.weatherplus.com/wxplocal/13285041/detail.html

    Btw, i put a thread up last week with live streaming audio/weather channels etc. (that's where i got the above from). So , it seems like a good time to link my blog page with said live streaming events! :whistling:

    http://hamspirit.wordpress.com/live-streaming-audio/

    edit: Daytona Beach webcam: http://volusia.org/beach/daytona.htm

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    Posted
  • Location: ipswich <east near the a14> east weather watch
  • Location: ipswich <east near the a14> east weather watch

    reg Andrea is it early in the season for something like this looking at the its heading for the keys track looks like it could go into the GULF OF MEXICO or am i reading it rong !

    OFFSHORE WATERS FORECAST FOR THE SOUTHWEST AND TROPICAL NORTH

    ATLANTIC AND CARIBBEAN SEA

    NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

    1130 AM EDT WED MAY 09 2007

    OFFSHORE WATERS FORECAST FOR THE CARIBBEAN SEA AND TROPICAL N

    ATLC FROM 7N TO 22N BETWEEN 55W AND 65W

    AMZ080-092130-

    SW N ATLC S OF 31N W OF 65W INCLUDING BAHAMAS

    1130 AM EDT WED MAY 09 2007

    TROPICAL STORM WARNING N OF 29N W OF 77W

    THIS AFTERNOON AND TONIGHT

    N OF 29N W OF 77W WINDS 30 TO 40

    KT DIMINISHING TO 25 TO 35 KT LATE TONIGHT. SEAS 10 TO 15 FT.

    ELSEWHERE N OF 27N W OF 74W S TO SW WINDS 20 TO 25 KT. SEAS 7 TO

    11 FT. REMAINDER OF AREA SE TO S WINDS 10 TO 15 KT EXCEPT NE 5

    TO 10 KT W OF BAHAMAS. SEAS 5 TO 7 FT IN NE SWELL EXCEPT 2 TO 4

    FT W OF BAHAMAS. SCATTERED SHOWERS AND ISOLATED TSTMS N OF 28N W

    OF 77W. SCATTERED SHOWERS AND TSTMS E OF 74W.

    THU AND THU NIGHT

    N OF 30 W OF 78W E TO SE WINDS 25 TO 35 KT.

    SEAS 8 TO 12 FT. N OF 27N W OF 75W S TO SW WINDS 15 TO 20 KT.

    SEAS 5 TO 7 FT. ELSEWHERE SE TO S WINDS 10 TO 15 KT EXCEPT NE 5

    TO 10 KT W OF BAHAMAS. SEAS 4 TO 6 FT EXCEPT 1 TO 3 FT W OF

    BAHAMAS. SCATTERED SHOWERS AND ISOLATED TSTMS N OF 29N W OF 75W.

    SCATTERED SHOWERS AND TSTMS E OF 70W.

    FRI

    N OF 29N W OF 80W E TO SE WINDS 20 TO 30 KT. SEAS 6 TO 8

    FT. N OF 28N W OF 78W S WINDS 15 TO 20 KT. SEAS 5 TO 7 FT.

    ELSEWHERE N OF 25N S TO SW WINDS 5 TO 10 KT. SEAS 3 TO 5 FT. S

    OF 25N SE TO S WINDS 10 KT EXCEPT NE 5 TO 10 KT W OF BAHAMAS.

    SEAS 3 TO 5 FT EXCEPT 1 TO 2 FT W OF BAHAMAS. SCATTERED SHOWERS

    AND TSTMS S OF 26N E OF 76W.

    SAT AND SUN

    N OF 25N S TO SW WINDS 5 TO 10 KT. SEAS 2 TO 4

    FT. S OF 25N SE TO S WINDS 5 TO 10 KT. SEAS 2 TO 4 FT EXCEPT 1

    TO 2 FT W OF BAHAMAS. SCATTERED SHOWERS OR TSTMS SE PART.

    FORECASTER BERG/CHRISTENSEN

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    Posted
  • Location: Larbert
  • Location: Larbert

    The GFDL model takes Andrea over mainland Florida, she plays about a bit, then heads back to the open waters of the NA, probably as a lesser hybrid than she is now.

    Infact, here's the latest bulletin:

    SUBTROPICAL STORM ANDREA INTERMEDIATE ADVISORY NUMBER 1A

    NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012007

    200 PM EDT WED MAY 09 2007

    ...POORLY-ORGANIZED SUBTROPICAL STORM MEANDERING OFF THE SOUTHEAST

    U.S. COAST...

    A TROPICAL STORM WATCH REMAINS IN EFFECT ALONG THE SOUTHEAST COAST

    OF THE UNITED STATES FROM ALTAMAHA SOUND GEORGIA SOUTHWARD TO

    FLAGLER BEACH FLORIDA. A TROPICAL STORM WATCH MEANS THAT TROPICAL

    STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...GENERALLY

    WITHIN THE NEXT 36 HOURS.

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

    INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED

    BY YOUR LOCAL WEATHER OFFICE.

    AT 200 PM EDT...1800Z...THE CENTER OF SUBTROPICAL STORM ANDREA WAS

    ESTIMATED NEAR LATITUDE 30.9 NORTH...LONGITUDE 80.0 WEST OR ABOUT

    100 MILES...160 KM...SOUTHEAST OF SAVANNAH GEORGIA AND ABOUT 135

    MILES ...220 KM...NORTH-NORTHEAST OF DAYTONA BEACH FLORIDA.

    ANDREA IS MOVING ERRATICALLY...BUT GENERALLY TOWARD THE WEST NEAR 3

    MPH. A CONTINUED SLOW MOTION AND A GRADUAL TURN TOWARD THE

    SOUTHWEST ARE EXPECTED DURING THE NEXT 24 HOURS. ON THIS

    TRACK...THE CENTER OF ANDREA IS EXPECTED TO REMAIN JUST OFFSHORE OF

    THE U.S. COAST THROUGH AT LEAST THURSDAY MORNING.

    MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER

    GUSTS. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 24

    HOURS.

    WINDS OF TROPICAL STORM FORCE EXTEND OUTWARD UP TO 115 MILES...185

    KM...MAINLY TO THE EAST OF THE CENTER.

    THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB...29.62 INCHES.

    SINCE THE HEAVIEST RAINS ASSOCIATED WITH ANDREA ARE EXPECTED TO

    REMAIN OFFSHORE DURING THE NEXT 24 HOURS... ANDREA IS NOT EXPECTED

    TO PRODUCE SIGNIFICANT RAINFALL OVER ANY LAND AREAS THROUGH AT

    LEAST THURSDAY MORNING.

    REPEATING THE 200 PM EDT POSITION...30.9 N...80.0 W. MOVEMENT

    TOWARD...WEST NEAR 3 MPH. MAXIMUM SUSTAINED WINDS...45 MPH.

    MINIMUM CENTRAL PRESSURE...1003 MB.

    THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT

    500 PM EDT.

    $$

    FORECASTER KNABB

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    Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

    My personal opinion is that it will die out as soon as it makes landfall, so i dont expect it to pose any problems or reach the Gulf Of Mexico and bomb, though it does prove that with the QBO now easterly and La Nina emerging, we could be in for a big one.

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    Posted
  • Location: Liphook
  • Location: Liphook

    From the looks of things its actually turned a little more tropical overnight then it was, in fact it now looks like a classic poorly organized tropical storm, as you'd expect at this time of year I suspect. It has more then one center of circulation as you normally find in a system like this that is poorly organized. Interesting convection has pepped up a little overnight on its eastern side however its starting to look like a classic asymmetrical system and is very lop-sided in regards to convection on its eastern side. I'll be very surprised if it strengthens and now its heading out of the gulf stream I suspect a slow weakening is likely, though right now the continued transition to more pure tropical system is keeping it at 45mph though how long before this stops as temps below the sea surface start to become less able to support such a system I'm not sure.

    It may not matter much anyway as the models are all forecasting wind shear to pick up again as a jet streak comes across and that should tear the convection on its eastern flank away from the LLC and finish it off. It doesn't appear likely that it'll be a long lived system as there does appear to be quite a few ways this one could die. It could absorb dry air from the SE states (indeed that is why the western flank is pretty bare of convection.) the shear will likely kill it in the end as well, the cool shelf water near Florida could kill it off before landfall (and is a major reason why the NHC drop it to a depression before landfall.) and so there is a number of ways it could dissipate. The best shot it has got at survival will be for the LLC (or at least the more dominant one!) to tuck into the convection on its eastern side, though if the shear does power p that will only give it an extra 6hrs or so before it is blown apart. Right now it does look like the LLCis already fairly exposed as the western LLC looks the more dominant.

    Landfall may or may not occur in Florida. The models still suspect it will but wit these multiple LLC systems its very hard to tell exactly where the overall broad circulation is. It may not matter for those who have drought in the SE states because the convection is fairly weak anyway on that western side and unless the center can cross close to the Gulf of Mexico then the main convection should remain teasingly just off-shore. (edit- latest NHC predictions now prog it to curve SSW-S-SSE and move very slowly while slowly decaying. One other tning that I didn't mention was the GFDL model is forecasting Andrea to strengthen after 60hrs again as it head sout to sea again, will be intresting to see what happens...)

    Still its a very early season storm and so it shouldn't be expected to last all that long but it is a nice easy start to what is expected to be a active season. Whatever happens with Andrea now should still be just warm-up for the rest of the season.

    By the way recon is heading into the system this afternoon.

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    Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet

    http://www.sfwmd.gov/org/omd/ops/weather/plots/storm_01.gif

    Looking at the model outputs, i dont think anybody has a clue where this storm will go...

    http://wxmaps.org/pix/hurpot.html#ATL

    As you can see from this link, getting into the Gulf Of Mexico would not make much difference, to see anything of note, it needs to be in the Carribean Sea which will not happen.

    I agree with Kold Weather, from hear on out i favour weakening.

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    Posted
  • Location: ipswich <east near the a14> east weather watch
  • Location: ipswich <east near the a14> east weather watch

    Subtropical Storm ANDREA Forecast Discussion

    --------------------------------------------------------------------------------

    Home Public Adv Fcst/Adv Discussion Wind Probs Maps/Charts Archive

    US Watch/Warning

    --------------------------------------------------------------------------------

    000

    WTNT41 KNHC 100831

    TCDAT1

    SUBTROPICAL STORM ANDREA DISCUSSION NUMBER 4

    NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012007

    500 AM EDT THU MAY 10 2007

    ANDREA CONTINUES TO APPEAR RATHER UNIMPRESSIVE...WITH LATEST

    SATELLITE IMAGERY AND RADAR INDICATING SOME WEAK PULSATING

    CONVECTION TO THE EAST OF THE CENTER WHILE THE WESTERN HALF REMAINS

    NEARLY CONVECTION FREE. SATELLITE INTENSITY ESTIMATES HAVE

    DECREASED TO 25 TO 30 KNOTS...AND THE INITIAL INTENSITY HAS BEEN

    ADJUSTED DOWNWARD CONSERVATIVELY TO 35 KT. AN AIR FORCE

    RECONNAISSANCE AIRCRAFT IS SCHEDULED TO INVESTIGATE THE SYSTEM

    LATER THIS MORNING TO PROVIDE A BETTER ESTIMATE OF THE INTENSITY.

    WATER VAPOR IMAGERY DEPICTS VERY DRY AIR SURROUNDING THE CYCLONE IN

    ALL QUADRANTS EXPECT FOR THE NORTH. LATEST SHEAR ANALYSIS FROM

    CIMSS SHOWS 20 KNOTS OF NORTHWEST SHEAR IMPINGING UPON THE CYCLONE.

    THIS COMBINATION OF SHEAR AND DRY AIR IS INHIBITING CONVECTION AND

    DISPLACING THE CONVECTION THAT DOES EXIST TO THE EAST OF THE

    CENTER. BOTH THE SHIPS AND GFDL GUIDANCE SUGGEST POSSIBLE

    STRENGTHENING. HOWEVER GIVEN THE CURRENT NORTHWESTERLY SHEAR AND

    THE ABUNDANCE OF DRY AIR...THE OFFICIAL FORECAST CALLS FOR GRADUAL

    WEAKENING AND DISSIPATION IN 96 HOURS...IF NOT SOONER. THERE IS A

    CAVEAT TO THE INTENSITY FORECAST...IN THAT A MID- TO UPPER-LEVEL

    LOW CURRENTLY OVER TEXAS MAY INTERACT WITH ANDREA IN 72 HOURS.

    THE CYCLONE HAS DRIFTED SLIGHTLY TO THE SOUTHWEST...AS A RESULT OF

    BEING EMBEDDED IN A LARGE DEEP-LAYER TROUGH. THE TRACK FORECAST IS

    A BIT COMPLEX. MOST OF THE MODEL GUIDANCE TAKES THE CYCLONE

    GENERALLY SOUTHWARD OVER THE NEXT TWO TO THREE DAYS...AS THE

    UPPER-LEVEL TROUGH THAT THE SYSTEM IS CURRENTLY EMBEDDED IN OPENS

    UP AND MOVES EASTWARD...AND THE LOW-LEVEL STEERING REMAINS WEAK. IF

    ANDREA STILL EXISTS AFTER 72 HOURS...THE UKMET...GFS...AND ECMWF

    FORECASTS A FRONT EXITING THE EASTERN U.S. PUSHING THE DISSIPATING

    CYCLONE EASTWARD.

    GIVEN THE UNCERTAINTIES IN THE FORECAST TRACK AND INTENSITY...THE

    TROPICAL STORM WATCH REMAINS UNCHANGED AT THIS TIME.

    FORECAST POSITIONS AND MAX WINDS

    INITIAL 10/0900Z 30.4N 80.0W 35 KT

    12HR VT 10/1800Z 30.2N 80.1W 30 KT

    24HR VT 11/0600Z 29.9N 80.2W 30 KT

    36HR VT 11/1800Z 29.7N 80.2W 25 KT

    48HR VT 12/0600Z 29.5N 80.1W 25 KT

    72HR VT 13/0600Z 29.3N 79.9W 25 KT...DISSIPATING

    96HR VT 14/0600Z...DISSIPATED

    $$

    FORECASTER MAINELLI

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