Tropical Wave in Central Atlantic (Is Invest 97L)

[HurricaneMaster_PR]

The 18Z FIM is noticeably weaker also than the 12Z FIM also:

It is also on a more westward track than the earlier

[Hurricaneman]

Here is how the 18Z GFS ends. This system combines with another system and creates this below recurving east of the United States:

not alot for sept 10. has it combined with a cold low or another tropical disturbnace?

that is a combination of pouch 25 and another wave currently over central Africa that recurve into each other, and become a major extratropical storm. By the way it has pouch 25 getting into the SE Bahamas before recurving instead of recurving around 60W like the 12zGFS

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[TheStormExpert]

So the trend is farther west and weaker.

[Hurricaneman]

So the trend is farther west and weaker.

actually as of now there is no clear trend except to watch its progression as it goes west

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

[ninel conde]

So the trend is farther west and weaker.

actually as of now there is no clear trend except to watch its progression as it goes west

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

hopefully there will be some convection to watch

[gatorcane]

Right now convection is on the decline big-time. Latest saved image of the area now over water just off the coast of Africa. Clearly it is going to need several more days to potentially get it's act together...

[ConvergenceZone]

At least the overall convection seems to be increasing a bit in the Atlantic and over Africa, perhaps a sign of things finally getting started.

[Riptide]

So the trend is farther west and weaker.

At the least, it is still a identifiable tropical disturbance; should be interesting to track.

[Hurricaneman]

The 0zGFS is quite a bit faster with this as this is at 13N 52W at 108 hrs as a broad 1013mb low

114hr is in about 13N 52W with a broad 1010mb pressure

120hr is in about the same spot with a broad low

123hr has a closed 1012mb low at about 13N 55W

138hr has a broad low at about 13N 57W

144hr weakens to a wave

156hr the MLC is at 14N 62W

168hr the MLC is at 15N 64W

174hr the MLC is in the same place as at 168hr

180hr the MLC is still stationary

204hr the MLC is at 15N 66W

228hr the MLC is at 16N 69W

240hr the MLC is at 17.5N 72W

264hr the MLC is at 18.5N 73W

288hr the MLC is at 19.5N 75W

312hr recurves the MLC out to sea

so basically the GFS has given up on the development of this wave

[Hammy]

If I recall, the GFS has been pretty much off and on with this one on development, I dont think it even went a full day's worth of runs going one way or the other for awhile on it.

[Gustywind]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
459 AM AST MON AUG 26 2013

THE GFS HAS DEVELOPED TROPICAL SYSTEMS IN EACH OF THE LAST
SEVERAL DAYS` RUNS...BUT IS NOT CONSISTENT IN THE STRENGTH OF
THOSE SYSTEMS. THE FIRST TROPICAL WAVE TO LEAVE AFRICA THIS WEEK
IS NOW MOVING TOWARD THE AREA...HOWEVER THE GFS HAS BEEN SHIFTING
THE CENTER OF THIS SYSTEM TOWARD THE CARIBBEAN WITH EACH
SUCCESSIVE RUN. THE LATEST MODEL RUN...THAT OF 26/00Z...SHOWS
ONLY A WEAK LOW PASSING SOUTH OF THE AREA ON THE DAY AFTER LABOR
DAY. THE ECMWF DOES NOT DEVELOP THIS LOW STRONGLY AND SHOWS IT
PASSING NORTHEAST OF THE LEEWARD ISLANDS IN THE SAME TIME FRAME.
THEREFORE IT IS TOO EARLY TO CONCLUDE ANYTHING ABOUT A TROPICAL
SYSTEM PASSING THROUGH THE AREA BEYOND SATURDAY AND THE FORECAST
WAS NOT ALTERED. OTHER LOWS CAN ALSO BE SEEN IN THE TROPICAL
ATLANTIC LATE IN THE 10 DAY PERIOD IN THIS MODEL RUN...BUT THE
NEXT ONE IS CURRENTLY TURNING NORTHWEST IN THE MID ATLANTIC.

&&

[Gustywind]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT MON AUG 26 2013

0% / 30%

A TROPICAL WAVE EMERGING OFF OF THE WEST COAST OF AFRICA IS EXPECTED
TO MOVE GENERALLY WESTWARD ACROSS THE TROPICAL ATLANTIC OVER THE
NEXT SEVERAL DAYS. SOME DEVELOPMENT OF THIS DISTURBANCE IS POSSIBLE
BY MIDDLE TO LATE WEEK. THIS SYSTEM HAS A LOW CHANCE...NEAR 0
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48
HOURS...AND A MEDIUM CHANCE...30 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 5 DAYS.

[NDG]

Models are backing away from developing this tropical wave, IMO.
At least backing away from developing this into a strong system as they were doing in previous runs.

[ninel conde]

shocked its still at 30%. as with all the others the part of the wave that might develop is totally devoid of clouds, forget convection.

[Alyono]

GFS AGAIN pushing back development to the "next" wave

I'm not convinced this is the one to develop

[ninel conde]

GFS AGAIN pushing back development to the "next" wave

I'm not convinced this is the one to develop

something needs to develop pretty soon or the peak will be gone.

[Blown Away]

GFS AGAIN pushing back development to the "next" wave

I'm not convinced this is the one to develop

something needs to develop pretty soon or the peak will be gone.

06z drops developing Pouch 25 and immediately develops a wave as it moves off Africa in 5 days then curves it out to sea in the mid Atlantic...

[tolakram]

The latest Euro vorticity does the splits. One area north of the islands while the other makes it to the western Caribbean.



Looking at the GFS vorticity, it scoots this wave west across the MDR, merges it with another area of vorticity near the islands, and then moves it NW.



In my amateur opinion the main problem seems to be determining how fast the wave moves and the timing of the MJO. A model that comes up with a weak MJO solution won't show much development. I wish I knew how the MJO was factored into these model runs.

[cycloneye]

No change.

A TROPICAL WAVE LOCATED OVER THE FAR EASTERN ATLANTIC IS EXPECTED
TO MOVE GENERALLY WESTWARD ACROSS THE TROPICAL ATLANTIC OVER THE
NEXT SEVERAL DAYS. SOME DEVELOPMENT OF THIS DISTURBANCE IS POSSIBLE
LATER THIS WEEK. THIS SYSTEM HAS A LOW CHANCE...NEAR 0 PERCENT...
OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS...AND A
MEDUIM CHANCE...30 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING
THE NEXT 5 DAYS.

[otowntiger]

GFS AGAIN pushing back development to the "next" wave

I'm not convinced this is the one to develop

something needs to develop pretty soon or the peak will be gone.

And that's not a bad thing! I'd love for all the prognostications to be wrong and we end up with a very rare inactive season. I know it won't be exciting but it is always interesting when mother nature keeps us guessing and all the experts are fooled.

It seems this will not be a Cape Verde long tracker season, if waves like this are doomed this time of year.