Atlantic Invest Thread 2008

[kold weather]

Well since we now have Invest 90LI'm creating this Invest thread. This for any systems that have been tagged as an invest but have not got the organisation of a tropical depression. Once that occurs with any invest a new thread will be opened for that system in question.

Anyway as I just said 90L has been tagged, its the area of convection currently in the W.Caribbean. Imagery reveals it has a weak LLC present that is fairly broad in nature. Convection has been developing around it over the past 12hrs since Alma's decay and indeed its quite possible that some of Alma's remains are within this invest as well. Whilst its nott well defined it does appear at the moment that 90L is heading steadily towards land and thus I'm not expecting development of it at least this side of the Yucatan however there is a chance that it will re-emerge into the BoC and if it does then depending on its latitude there is always a chance that it will develop a stronger and better defined circulation with a more organised convective pattern, however that is all a good 2-3 days away yet so we shall see what happens. GFS has been hinting at this occuring so its next 2-3 runs will be very interesting to see if it has a good grip with the system in question.

Anyway here we are I suppose, not the offical start of the season but its so close it may as well be!

Edited May 30, 2008 by kold weather

[Cookie]

thanks kold great read as ever lets hope for a great season

[kold weather]

Well we have Invest 91L however its heading towards south America at a fair clip and it appears that what LLC was present a few hours ago when it was declared as an invest is now gone and has become an open wave again. Convection is pretty decent along the whole wave axis and therefore it may need to be watched in the western Caribbean.

[Cookie]

thanks for the update I wish something would happen

[tinybill]

evening all i found this site might be some good

http://ralphstropicalweather.homestead.com...WeatherOut.html

[Cookie]

wow that site is good thanks for the link

[Iceberg]

92L has been initialised very close to Africa, HWRF has taken a liking to it and very quickly makes it a boardline Cane.

More to follow but I am in a meeting atm.

Matt

Sat image

[Iceberg]

This looks like being rather a boring system but hey it's something.

Attached are the predicted paths and Ships which makes it very strong.

It looks like it will quickly pass over into cooler waters and a more hostile environment though.

However before that we have a system that could very quickly get it's act together.

The Ridge will almost certainly weaken preventing a land hit.

Also SST path and Phase charts shows the warm core. From 27C and below intensification pretty much stops.

[tinybill]

This looks like being rather a boring system but hey it's something.

Attached are the predicted paths and Ships which makes it very strong.

It looks like it will quickly pass over into cooler waters and a more hostile environment though.

However before that we have a system that could very quickly get it's act together.

The Ridge will almost certainly weaken preventing a land hit.

Also SST path and Phase charts shows the warm core. From 27C and below intensification pretty much stops.

http://www.nhc.noaa.gov/

they like it!!!!!!!!!

[kold weather]

I've not got much time to talk about Invest 92L but this far east its very rare to see a system form at this time of year however shear is low (indeed SHIPS has very low shear by 72hrs) SAL is very low to the north with the wave previous to this one taking the main blow and SST's are above normal in the region closer to what you'd expect in August.

Models recurve this system and thats probably quite likely as the high won't peak in strength till August though the models likely do have a right bias and could well be too quick in taking a more NW track. IMO I favor a WNW track out to 48-72hrs, then a more westerly track probably out to 50-60W then a more direct NW track. If it can strengthen and develop then we could see something in 72hrs. SST's then indeed do drop though shear remains very low and once it gets past the lower temps it gets back into the 27-28C region. it's here the ECM powers this wave up into what appears to be a powerful hurricane.

We shall see...

[Iceberg]

ECM does indeed take it to a powerful hurricane, a real possibility but a long way out yet.

A good 72 hrs does seem to be ahead though.

[kold weather]

Yep convection starting to refire now over any weak circulation that is present now we are getting out of the durinial min and thats a good sign, will be intresting to see what this looks like at 9am tomorrow...

Also as for the ECM, that track would not be all that far away from Bermuda, only would need a fairly small shift in the vector of the system it has for a little while to make that a hit. Still we shall have to wait and see.

would be ironic to see another Bertha be an early Cape Verde system. IMO about 50-50 chance of formation from this wave in the next 72hrs, compared to the average at this time of year that very high indeed.

[Iceberg]

Sat is rather patchy out there however it still looks in reasonable state.

An interesting guidance from the Met this morning. Which does not recurve the system

NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 12 HOURS

FORECAST POSITION AT T+ 12 : 11.4N 20.5W

VERIFYING TIME POSITION STRENGTH TENDENCY

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

12UTC 02.07.2008 11.4N 20.5W WEAK

00UTC 03.07.2008 11.8N 21.9W WEAK LITTLE CHANGE

12UTC 03.07.2008 12.5N 24.5W WEAK LITTLE CHANGE

00UTC 04.07.2008 12.9N 27.9W WEAK LITTLE CHANGE

12UTC 04.07.2008 12.2N 30.5W WEAK LITTLE CHANGE

00UTC 05.07.2008 13.0N 32.3W WEAK LITTLE CHANGE

12UTC 05.07.2008 14.5N 35.2W WEAK LITTLE CHANGE

00UTC 06.07.2008 15.4N 38.5W WEAK WEAKENING SLIGHTLY

12UTC 06.07.2008 17.0N 42.0W WEAK LITTLE CHANGE

00UTC 07.07.2008 16.9N 46.3W WEAK LITTLE CHANGE

12UTC 07.07.2008 17.9N 49.7W WEAK LITTLE CHANGE

00UTC 08.07.2008 18.0N 53.2W WEAK LITTLE CHANGE

02/0000 UTC 11.9N 19.4W T1.0/1.0 92L -- Atlantic Ocean

A classification of T1 has been made overnight(25kt) a good chance that this will become TD 2 today.

[kold weather]

Possibly Iceberg though they will probably wait for quikscat and also classification of 1.5 before they upgrade. Its slowly but surely getting there though with some deep convection present. LLC looks to be a little displaced to the east of that convection however and there is hints of shear, esp on the southern side of the convection. We shall see what happens!

[kold weather]

Quick update:

92L: Looks a little better then this morning with a clear LLC present and also moderate-deep convection near the center as well, still not quite at TD status yet but it isn't all that far away IMO. Model tracks are taking this wave firstly to the west and then off to the NW as a upper weakness opens up in the central Atlantic.

The exact track will be key because in about 36-48hrs time it will cross cooler waters and obviously the further north this gets the cooler the waters and thus even if something develops now it may weaken until it reaches about 40W where temps rise again. Shear should remain low till at least 144hrs, beyond that is a little hard to tell. air is also quite moist around the system given the time of year and how typically we should have a lot of SAL. Therefore I don't see any reason other then maybe the cooler waters coming up that should mean this system won't develop eventually. Could end up forming very far east for the time of year.

93L: Just been tagged 93L. This a little wave that has developed increasingly impressive convection just over the Lesser Antilles. Circulation is evident with the wave which is very interesting however the main problem for this wave is that there is huge shear is present just to the west, between 30-50kts which will kill this system probably soon enough. There is probably a 12-24hrs window for any development which may be a little short before shear really takes a knotch up and destroys this system.

Anyway overall some activity for July, with 2 invests which for early July is pretty impressive!

[Somerset Squall]

In addition to 92L (which we have been discussing), there is now invest 93L, to the east of the Lesser Antilles. This new invest is much nearer the warm waters of the Caribbean, however, there appears to be strong shear to the west of the invest. I wouldn't like to really say what chances this one might have of developing. The environment seems to me to be marginal at best.

Edit: haha, you beat me to it Kold

Edited July 2, 2008 by Somerset Squall

[Iceberg]

93L does seem very lucky really.

92L is looking nicer again this morning, Scatt winds indicate 25Kt at bare minimum and probably enough to support 30Kt in a tight circulation.

It's difficult to see exactly how centre the now persistant convection is but my gut tell me this would be TD2 if this were closer to the states. However data is still fairly sketchy.

[Iceberg]

Sorry for the half asleep gramma above.

Latest from NHC

"ENVIRONMENTAL CONDITIONS APPEAR

CONDUCIVE FOR SOME ADDITIONAL DEVELOPMENT AND THERE IS THE

POTENTIAL FOR IT TO BECOME A TROPICAL DEPRESSION AT ANY TIME

TODAY."

[Jack Wales]

Now officially TD2...

NOAA

Intensification up to 55kt forecast by noaa with the ships/gdfl models forecating TD2 to reach hurricane status within 5 days.

[Iceberg]

Indeed just to round it off in this thread the official update from NHC.

Tropical Depression TWO Forecast Discussion

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

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

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

000

WTNT42 KNHC 030859

TCDAT2

TROPICAL DEPRESSION TWO DISCUSSION NUMBER 1

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008

500 AM EDT THU JUL 03 2008

THE STRONG TROPICAL WAVE AND SURFACE LOW OVER THE EASTERN ATLANTIC

OCEAN HAS ACQUIRED ENOUGH ORGANIZED CONVECTION TO NOW BE CONSIDERED

A TROPICAL DEPRESSION. SATELLITE IMAGES INDICATE THAT A STRONG

BURST OF CONVECTION HAS PERSISTED FOR OVER 12 HOURS NEAR OR JUST

WEST OF THE APPARENT CENTER OF THE SYSTEM. BANDING FEATURES ARE

ALSO BECOMING MORE PRONOUNCED IN THE NORTHWESTERN PART OF THE

CIRCULATION. THE INITIAL INTENSITY OF 30 KT IS BASED ON A QUIKSCAT

PASS FROM LATE YESTERDAY THAT SHOWED SOME RELIABLE 25-30 KT WINDS.

IT SHOULD BE NOTED THAT MOST GLOBAL MODELS...ESPECIALLY THE

GFS...SUGGESTED THE POSSIBILITY OF GENESIS IN THIS AREA OVER A WEEK

AGO...A REMARKABLE ACHIEVEMENT.

[Mesosphere]

Invest 97E has formed in the Eastern Pacific Basin :-

ZCZC MIATWOEP ALL

TTAA00 KNHC DDHHMM

TROPICAL WEATHER OUTLOOK

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

500 AM PDT SAT JUL 5 2008

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE..

1. SHOWER AND THUNDERSTORM ACTIVITY HAS INCREASED THIS MORNING IN

ASSOCIATION WITH AN AREA OF LOW PRESSURE CENTERED A COUPLE HUNDRED

MILES SOUTH OF ACAPULCO MEXICO. DESPITE UPPER-LEVEL WINDS THAT

APPEAR ONLY MARGINALLY CONDUCIVE FOR DEVELOPMENT...IT IS POSSIBLE

THAT THIS SYSTEM COULD BECOME A TROPICAL DEPRESSION WITHIN THE NEXT

DAY OR TWO AS IT MOVES SLOWLY WEST-NORTHWESTWARD.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE

NEXT 48 HOURS.

$$

FORECASTER KNABB

East Pacific Floater 1 has been positoned on Invest 97E

http://www.ssd.noaa.gov/goes/flt/t6/loop-vis.html

Edited July 5, 2008 by Calum

[Cookie]

what a bad name floater one!

[Mesosphere]

what a bad name floater one!

:lol:

[kold weather]

Right now we have invest 94L in the mid-Atlantic. Still attached to the ITCZ but does seem to be slowly organising and I'd guess we will have a TD in the next 18-36hrs. Right now its at a very low latitude and came from Africa about 4 days ago and has found a very favorable region with low shear, high heat content and low SAL and therefore I do foresee development.

I wil make a more indepth post sometime tomorrow but right now Ne Caribbean has to watch this system very closely, could well see this as a hurricane by that time, of course as I said very early days right now!

[Iceberg]

Agree Kold this won't be 94L for long

Below are ships etc.

GFDL takes it very quickly to a Cane (36hrs) and then to a CAT 3.

Floater 2 is currently over it.

Circulation look good and organisation is getting better and better.

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...

080713 1200 080714 0000 080714 1200 080715 0000

LAT LON LAT LON LAT LON LAT LON

BAMS 8.9N 37.2W 9.3N 38.5W 9.4N 39.8W 9.6N 41.7W

BAMD 8.9N 37.2W 9.3N 39.0W 9.8N 40.7W 10.1N 42.5W

BAMM 8.9N 37.2W 9.4N 38.9W 9.9N 40.4W 10.0N 42.2W

LBAR 8.9N 37.2W 9.4N 38.8W 9.9N 40.8W 10.3N 42.9W

SHIP 25KTS 32KTS 42KTS 48KTS

DSHP 25KTS 32KTS 42KTS 48KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...

080715 1200 080716 1200 080717 1200 080718 1200

LAT LON LAT LON LAT LON LAT LON

BAMS 9.6N 44.2W 9.6N 49.8W 8.5N 55.6W 7.6N 60.9W

BAMD 10.4N 44.9W 10.6N 50.3W 10.2N 56.2W 10.3N 62.3W

BAMM 10.0N 44.6W 9.8N 50.1W 8.8N 55.7W 8.0N 61.5W

LBAR 10.7N 45.4W 12.0N 51.2W 12.7N 57.3W 11.5N 62.5W

SHIP 58KTS 73KTS 82KTS 80KTS

DSHP 58KTS 73KTS 82KTS 53KTS