Invest Thread

[kold weather]

Hello everyone. now the hurricane season is near all posts about Invests shall be made in this one or moved into this thread to try and keep the forum tidy. Once the system has become a depression/storm then a new thread shall be made.

Anyway our new Invest, 92L has recently been classed an invest from the system that is mentioned in the last thread I posted din on here about other may interests. Pretty much the stuff I talked about in my last post still stands and so rather then re-write the whole thing I'll just quote my last post, note chances of development now have to have increased with the addition of it becoming an invest:

Amazingly enough that are of disorganized convection I mentioned on the 19th is still here in disorganized form!!!

Not much to talk about in regards to it right now, but overnight there has been an impressive flare-up of convection in the Yucatan channel. doesn't appear to be any circulation with this but its a decent convective mass right with a upper trough nearby drawing up the moisture for the convection. Its not much of a threat right now until it can develop some sort of circulation, if it does then the convection is more then deep enough for it to be taken noticed off, esp its position as well given the models track it into the Gulf of Mexico and the GFS does develop it into a closed circulation, in other words a tropical entity. The model phase charts suggest that if it does form it will be likely subtropical in nature, probably due to the upper trough that is nearby and the shear that is present still---which is still blowing the convection quite strongly off to the SE looking at the visables.

Still its something to watch and it has a small chance i suppose, though it is just a small chance right now given the lack of organization present with it, if it gains a closed circulation despite of the shear, then things become a little more interesting.

NOTE last line- currently loops are starting to show the cyclonic circulation is getting better established.

Edited May 31, 2007 by kold weather

[Paranoid]

Any chance of this becoming a depression or even a weak TS today? Two pre-season storms in one season has got to be pretty rare.

[Somerset Squall]

It seems upper level winds are becoming less favourable with time now, so the chance of a tropical depression is decreasing, although the potential is still there.

WIDESPREAD CLOUDINESS AND DISORGANIZED SHOWERS AND THUNDERSTORMS

EXTEND FROM CENTRAL AMERICA NORTHEASTWARD OVER THE WESTERN

CARIBBEAN SEA...WESTERN CUBA...AND PORTIONS OF FLORIDA. THIS

ACTIVITY IS ASSOCIATED WITH A BROAD AREA OF LOW PRESSURE NEAR THE

EASTERN YUCATAN PENINSULA. WHILE UPPER-LEVEL WINDS ARE GRADUALLY

BECOMING LESS FAVORABLE...THIS SYSTEM HAS SOME POTENTIAL FOR

TROPICAL OR SUBTROPICAL DEVELOPMENT OVER THE NEXT DAY OR SO AS IT

MOVES NORTHWARD INTO THE SOUTHERN GULF OF MEXICO. REGARDLESS OF

DEVELOPMENT...LOCALLY HEAVY RAINS ARE EXPECTED ACROSS WESTERN CUBA

AND PORTIONS OF THE FLORIDA PENINSULA DURING THE NEXT COUPLE OF

DAYS. PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL WEATHER SERVICE

OFFICE FOR MORE DETAILS.

[kold weather]

Recon is there right now, it does look like winds are high enough to be classed as a tropical feature however the key things they are looking for right now would be a warm core. This is the proof that the system is warm cored and given the winds have already been reported upto 30kts it would be enough, indeed flight level winds of 42kts have been found, which is possibly enough enough for TS/STS classification. Also the other issue as always is whether the system has a closed low level circulation. Recent recon suggests its close but we've yet to find proof its totally closed.

However the key issue is it really tropical at all?

Phase charts seem to be a little split. From its appearence it does look like a typical lop-sided hybrid system with the main convection displaced to the north and east of the center as you'd expect. Also note that the near the center of the low and how displaced the convection is from the center, while ther eis some more shallow convection close to the center with the more beefy showers close to Cuba, where the highest winds are probably likely given the decently cold cloud tops being reported.

Whatever the case there is no absence of moisture present with this system, the upper trough that is nearby is providing a lot of moisture and general instablity for this hybrid system to work with which is of course great news for Florida and the SE states in general providing it takes the western track which is looking more and more the case right now (well done to the NAM model for spotting this) and with a general track up the eastern gulf of Mexico towards either East Flroida or the Panhandle.

Whatever the track in terms of development it probably won't have the time nor the atmopshere to get much stronger then it is right now. Its being rapidly driven towards a weakness to its north. In terms of development prospects there is quite a lot of shear nearby thanks to a jet streak, though a weak upper high did form yesterday which eased the shear just a touch and may have helped make a difference. The next issue for this system is obviously going to be the water temps to its north wher eits heading, which really aren't great for tropical development, though if the system is classified as tropical the temps may just be high eonugh to sustain the system.

So whats going to happen next?

All depends on what recon finds. Looks like the temp profiles are just about sharp enough from the outer bands to the center to be tropical in nature and so now its down to that all important west wind....if its found, then TD2/TS Barry is here, if not then it'll remain 92L and probably stay that way for good...

[kold weather]

Update---West winds found by recon with winds reported upto 40mph with sea surface pressur eof 1003mbs...I think a new thread might have to be made for a short lived tropical storm Barry!

RECCO Observation

Storm Name: INVEST (BBL)

Mission Number: 01

Flight ID: AF307

Observation Number: 09

Time: 1842Z

Latitude: 23.6°N

Longitude: 85.6°W

#NAME?

Turbulence: None

Flight condition: Clear

Pressure Altitude: 1000 feet

Flight level wind: W (270°) @ 44 mph

Temperature: 72°F

Dewpoint: N/A°F

Weather: Overcast Skies

Sea level pressure: 1003 mb

Surface Wind: W (270°) @ 40 mph

Remarks: None

EDIT 20.00---Even higher winds have just been reported by recon, winds at 56mph have been found at flight level, looks certain its going to be upgraded now...

If its not I'll be quite frankly shocked, strong convection going up on the northern flank of the system closer to the center where those winds are being reported, this new firing convection is very suggestive of it being a pure tropical system rather then a hybrid as I suspected before.

Pressure---1000mbs

Edited June 1, 2007 by kold weather

[SxK]

I am in Kissimee just outside of Orlando in Florida.

Raining here already but no real wind. I expect we will feel the effect of TS Barry at some stage.

[Calrissian]

Woo hooooo, June 1'st, and we've 2 names already.

Barry is desperately welcome though on it current track, they have those 'bugaloo fires' that need dealing with, never mind the current drought in Florida.

[Iceberg]

A wave in the Carb has just been progressed to Invest 94L.

Few details as yet but circulation is evident with sporadic convection.

[Iceberg]

GFDL takes this upto a CAT 1 (eventually), Although it very quickly takes her to a TS to hit florida.

[Iceberg]

She's in a very favourable low shear environment.

For info she isn't the big blob of convection but the little circulation in the box.

[kold weather]

A new invest to have over in the next few days, 95L.

Not really much to say about this one right now to be honest because my focus has been elsewhere however it doesn't look like it has any circulation at all with it and observations from E.Florida also don't suggest any low pressure development right now. It is from the looks of things ust a alrge convective mass. Given its current placement though I can see why you'd give the system an invest, the SST's in that area appear to be high enough now to support tropical development, at least minimal, though it does appear to be sheared a touch now however which further makes development unlikely.

As for its future, its best shot will no doubt be as it exits NNE/NE towards the gulf stream, already this year this has helped to give energy to Andrea and its going to be the best shot for this invest. chances are low given it has no circulation at all and would be starting from the very start and once north of the gulf stream it will die away pretty rapidly. Shear is also a touch higher then I'd want for development but given the time of year every decent convective blow-up needs watching I guess.

Sadly all rain is just to the east of Florida, Florida could do with some rain at the moment but unless it gains some westerly movement to it whichthe models aren't really forecasting at the early stage then it may be just out of reach for some of them.

[kold weather]

Well 95L is gone however last night we got 96L which was declered from a wave that came off Africa. currently the wave is on a weakening trend however this morning convection had become quite concentrated clsoe to a circulation which had developed at the mid-level and recent Sat.passes have shown that the system may well have a small Low level circulation and if this is true then it may wlel have a fighting chance at becoming Td3.

however there are problems right now is that in that region of the world, the SST's are still fairly marginal for development right now. There is also an area of much more stable air and dust to its north being circulated by the Azore shigh to its north. It appears right now that invest 96L is taking in some of that drier air with some stable stratocumulus present because of the cap in the airmass to its north and the invest's inflow on its northern side looks like its taking in some of that drier air. The other issue is the increase of shear that the models are forecasting. Currently 96L is located on the northern side of the Inter tropical convergance zone with the hostile environment to its north. The chances of its development right now are fairly decent compared to other invests and its nearly identical in placement to Dennis/emily in 2005 though obviously the set-up is different to that one.

I'll keep an eye on it, if its gonig to develop it'll be voer the next 24hrs I suspect. Its track should takre it generally west, maybe at times once it gets closer to the Cairrbean more WNW and if it can reach the Caribbean then it will likely get another shot at development if it doesn't develop this time around.

[Iceberg]

98l has been located, a def fish but looks like it could well spin back into the atlantic and help to reinforce the hp ridge.

It could well open the doors a bit though as the ITCZ is allowed to move further north.

Tracks all pretty consistant and GFDL takes it to a cane, just !.

There is a floater overhead, good moisture with lots of precip. There is also some rotation in evidence.

Matt

[kold weather]

Right new invest has formed just to the east of the Bahamas. It has to be said the system is a mess right now in terms of convection and it has formed it appears from a frontal system which is stretching away NNE into the Atlantic. The reason it probably has attained invest status IMO is becuase of the eastern lobe of convection. This mass of convection to the east of the frontal band does look somewhat detached though probably not completely. with such a messy mass of convection its pretty hard to see if ther eis any real cyclonic turning present within the mass of convection. It does appear to me however there is some cyclonic turning on the eastern mass of convection though its clearly not closed and its difficult to tell at what level the circulation is at, though quickscat does hint at some turning occuring at the surface as well and Sat.loops do rather suggest this may be the case.

As for its future, there looks to be a upper low to the systems NE which is driving itself NE and I strongly suspect that the invest will get dragged along up to the NE. This backed up by the models which all take it up NE and out into the Atlantic by 96hrs. Now exactly what happens with this systems strength is the big unknown. The GFDL takes this upto minimal hurricane strength while the HRWF barely closes the circulation and take sit upto 24kts. The ships are also quite liking it taking it upto 60kts, just under cat-1 status and is quite close to the GFDL. However despite this I'm having a relaly hard time seeing this system developing and I'm usually quite agressive with my forecasts in terms of strength but I'm not really seeing this. IF it can close its circulation off and become even more detached from the front to its west then it may have a shot at becoming a sub/tropical cyclone though I doub tit'll be nearly as strong as some models are predicting right now.

Anyway here it is right now, quite a mess BUT I suppose it may need wathcing given the heat content can support tropical systems and the shear doesn't look too severe as lnog as the front doesn't catch up with it, indeed if its lucky the shear may help to ventilate the system IF it develops. Its also helped by the fact that its progged to move in the same direction as the upper low which will help to reduce the relative shear some more. This may be the reason why the GFDL strengthens the system quite as much as it does IMO. Still it has got a circulation which does give it a fighting chance if it can pump out some better organised convection. Possible for it to develop into a dsiorganised TD3 and maybe a weak sub/tropical storm. worth watching tohugh because shear does seem to be increasing to the systems north thanks to the tigthening of the ULL and the developing ridge to the ULL NE which may wipe out any net gain from moving in tandem with the ULL.

Edited July 28, 2007 by kold weather

[mettalfabrik]

quote from NHC this morning

...SPECIAL FEATURE...

SURFACE TROUGH IS LOCATED FROM 29N72W INTO THE CENTRAL BAHAMAS

TO 22N76W. ENVIRONMENTAL CONDITIONS ARE FORECAST TO BECOME MORE

FAVORABLE FOR TROPICAL CYCLONE DEVELOPMENT AS THE SYSTEM MOVES

NORTH-NORTHEASTWARD OVER THE NEXT DAY OR TWO. RIDGING ALOFT

COVERS THE AREA SURROUNDING THE TROUGH AND SCATTERED SHOWERS AND

TSTMS ARE LOCATED FROM 24N-30N E OF TROUGH TO 71W.

[kold weather]

I've not got much time to update about this set-up but convection has improved a little last night and the feature has further detached from the frontal system. shear still seems to be coming up from the SW though actual relative shear isn't quite as high. System has quite a strong Mid level circulation present with it but no signs of a LLC right now tohugh without recon its a little hard to know. By the way recon has cancelled its flights into 98L, probably because of its track and the only threat is to Bermuda and evn then the system shouldn't be that strong.

Still has a shot at becoming a sub/tropical depression howeer and that window is open for another 24-48hrs before baroclinic forces start to play their part and deepen the system anyway.

[kold weather]

Not really much to add this morning about Invest 98L as nothing has changed too much. Still looks like a mid level circulation is present with convection to its east but it still lack any real sort of organisation with some northerly/NNE shear still pushing the convection northwards and though the convection is regernating quite readily it may well be a combo of the MLC and also it may be the shear itself which is helping to cause a certain amount of instablity on the eastern side of the system.

SAtelite imagery also suggests that the system does have a low level circulation as well but this is well dispalced from the convective mass which is yet another strong sign of of the shear that is present. IF its a closed low then if the system can organise its convection better then it may deelop but right now the convection is well displaced and so is a disorganised mess.

Anyway 98L probably has 24-36hrs left to develop as it will continue to head NNE into cooler waters soon and it will start to feel the effects of the jet stream and start to deepen in a Baroclinic fashion rather then barotropic. If shear does relax at all then with a strong MLC so it could develop but right now I don't see any real signs of shear easing and while its convectivly active it has a shot its fighting a losing battle.

Anyway her eis the latest image of the system, note the detached LLC with the convection to its east. Have to say with that close up it does rather look like a subtropical system is present rather then tropical, would make sense given the shear present and the present location of the system where the heat content isn't that impressive plus the fact the front isn't that far away even now. anyway here it is:

Edited July 30, 2007 by kold weather

[kold weather]

Hahaha!!!

I make a post about the wave in the central Atlantic in the wave thread and just as I do that the NHC make it Invest 99L!

Anyway I see little point of making a completely new post given notihng has really changed bar giving it a number so I'll just quote my previous post (note my comment about invests!):

Wave mentioned here looks very likely to be the next invest and system we need close watching, Sat.Imagery shows decent convection present at the moment which flared up last night with some low level cyclonic turning present though its a little hard to tell whether its a closed low or not, I'd suspect not right now but its needs watching as convection is plentiful though it is a touch ahead of the main wave axis which is around 44-45W.

Anyway wave is currently heading westwards in a pretty favorable environment. Mid level moisture is decent though there is drier air to the north which may surpresses the northern edge if the system gets going. Shear also shouldn't be too much of an issue from the looks of things as its heading into an area right now of limited shear with generaly only 5-10kts present which isn't going to prevent a closed low forming and indeed if there isn't one already present given the favorable condtions presently chances are it will start to develop one sooner rather then later. SST's also look good enough and while the heat content is a touch marginal it is on the right side of marginal for a tropical system to form, esp given the condtions as well that are present.

So this is one to watch for the future given the good set-up ahead. Its current lattiude is quite southerly and a strong subtropical high is building to its north as well presently which should keep the wave on a generally westerly track. On its current track and latitude I'd have thought it could be a sizeable risk to the Caribbean, esp given how high the heat content is presently there.

Reduced 84% http://www.netweather.tv/forum/index.php?a...st&id=43401 800 x 600 (48K)

The only other new thing we will see is the tropical models running on the 12z round and we will also see the SHIP guidence as well as having a floater over the system, looking quite likely we could see something from this, something that is totally tropical for once rather then hybrid and subtropical!

Not much in the way of negatives for this system up ahead for a little while so development is strongly favored.

Edited July 30, 2007 by kold weather

[kold weather]

Basic info summing up what is going on right now in the Atlantic:

For the North Atlantic...Caribbean Sea and the Gulf of Mexico...

Shower and thunderstorm activity associated with a low pressure area

centered about 175 miles west-northwest of Bermuda has become

better organized this morning. Environmental conditions are only

marginally favorable for significant development. However...the

system could become a tropical or subtropical cyclone before

merging with a frontal boundary in a couple of days as it moves

northeastward around 15 mph.

An area of cloudiness and showers located about 950 miles east of

the southern Windward Islands is associated with a westward-moving

tropical wave. This area shows signs of organization...and some

slow development of this system is possible during the next couple

of days.

Elsewhere...tropical cyclone formation is not expected during the

next 48 hours.

$$

Forecaster Brown/Pasch

Also it looks like 98L is starting to becoming a little better organised with the LLC moving closer to a convective burst just to the NE...it looks a LOT like Barry did when they upgraded it as it happens. It chances have increased since this morning, still not exactly stunning but it does look like a suntropical depression to me now, esp if the eastern LLC (closest to the convection) becomes the more dominant one

As for 99L first models suggest it will head into the Caribbean. SHIP intensity guidence suggests that slow development will occur with it reaching 76kts by 120hrs which would be hurricane strength...howveer the models are not going to have a good grip on a system that doesn't evn have a circulation so you don't have to read much into that forecasted strength.

Edited July 30, 2007 by kold weather

[londonsnow]

forgive me if this a rather obvious question but isnt the season rather late this year in the carribean?

[kold weather]

Not really, we are still a little ahead of the average as it happens in terms of numbers though not by a lot now it has to be said. min you if either 98L or 99L form this week then that would push back above average again. The season usually ramps up over the next 15-20 days to a peak in late August through to Mid September. Either side you usually get 1-2 storms/hurricanes on average. Looking like this season is going to start getting buiser in the next 10-15 days, I've been hinting at that on the model thread in the summer forum for the last week or so...

Edited July 30, 2007 by kold weather

[londonsnow]

Not really, we are still a little ahead of the average as it happens in terms of numbers though not by a lot now it has to be said. min you if either 98L or 99L form this week then that would push back above average again. The season usually ramps up over the next 15-20 days to a peak in late August through to Mid September. Either side you usually get 1-2 storms/hurricanes on average. Looking like this season is going to start getting buiser in the next 10-15 days, I've been hinting at that on the model thread in the summer forum for the last week or so...

thanks kold. LS

[Iceberg]

Not much time to update but 99l looks a real corker, I suspect looking at visual that an ragged LLCC is already there it has the classic look of a tight start up. Conditions look to be very favourable for development with some very warm water ahead. Certainly the first real potential of the season, GFDL takes it to a boarderline CAT 2 (with the usual GFDL issues of assuming an already closed circulation which is not evident !). The Tracks will take her into the upper GOM from the Carib though and a CAT 3 or more is def a possibility longer term, still early days though, but one I will watch will a great deal of interest.

The other Invest could still develop into a CAT 1 before entering extra tropical transition.

[Iceberg]

After looking at 98L an LLCC is clearly visable on Visual see diagram below.

It is however very exposed with no precip over the centre, hence it's not got the ability to crank up. Shear seems to be taking a toll even though it's not excessive.

[dvdfjojo]

forgive me if this a rather obvious question but isnt the season rather late this year in the carribean?

Found this graphic on the nhc site which illustrates how quiet a part of the season we are in, compared to the peak in mid-September. Here's the full link - http://www.nhc.noaa.gov/pastprofile.shtml

The wave train coming out of Africa seems to be pretty intense at the moment so I would think there will be plenty to watch in a few weeks time.

Edited July 30, 2007 by dvdfjojo