ATL: Ex-Tropical Storm GASTON - Discussion

[Steve]

>>Obviously then, while someone noted 7 members showing Cat 1 intensity, not all of them are independent.

My bad. I figured that was understood. FWIW I'm on record for no gut feeling either way, so I'm just watching. But that's a reason to at least watch even if it doesn't verify.

[supercane]

Maybe this will be the next TCFA!!! LOL

Got me going there for a while! Couldn't find verification of this on NRL and was wondering what's going on.

[HURAKAN]

Maybe this will be the next TCFA!!! LOL

Got me going there for a while! Couldn't find verification of this on NRL and was wondering what's going on.

I guess the powerpoint works!!!

[fasterdisaster]

I have a theory that Gaston's remnants will cross Honduras or around there and enter the Pacific. We will continue for weeks to watch for any redevelopment as Gaston hobbles into the CPAC basin and then the WPAC basin. Gaston will refuse to become a typhoon and so crosses Southeast Asia into the Indian Ocean. The forum will be extremely concerned that poverty-ravaged areas of the world will be hit with an intense cyclone. The wave will still refuse to develop and end up running into Somalia or around there. Gaston's remnants will spend the next few weeks gathering convection over the Sahara. Finally any remaining thunderstorms will come off West Africa into the Atlantic. By this time the 2011 hurricane season will have started and Gaston will become a Category 5 hurricane and kill everybody. The End.

[Ivanhater]

Good discussion so far with differing opinions. Keep it respectful, however.

[supercane]

ASCAT scrapped the western edge:

Based on the 00Z best track:
AL, 09, 2010090700, , BEST, 0, 175N, 590W, 30, 1011, LO, 34, NEQ, 0, 0, 0, 0, 1013, 170, 75, 0, 0, L, 0, , 0, 0, GASTON, S,
lack of west winds concerning for degeneration to wave.

[Recurve]

Will it stay an open wave? Maybe rain for areas that need it, but no damaging storms?
Knowing how waves sometimes drench us, I'm hoping it doesn't cause flooding/mudslides in PR, because it looks like it will at least have some convection by the time it gets there.

[supercane]

Microwave also not too impressive:

[ROCK]

that microwave image looks old....the LLC is still trying to fire convection...we might be looking at a better appearance tomorrow morning...

http://weather.msfc.nasa.gov/GOES/goeseasthurrir.html

[WeatherGuesser]

Just looks like normal clouds, nothing special at all right now.

[Shuriken]

Will it stay an open wave?

Who said it was an open wave?

As far as my eyes see, it's still a closed circulation.

[Brent]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT TUE SEP 7 2010

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM HERMINE...LOCATED ABOUT 10 MILES SOUTH-SOUTHWEST OF
HARLINGEN TEXAS.

DISORGANIZED SHOWERS AND A FEW THUNDERSTORMS OVER THE LEEWARD
ISLANDS AND ADJACENT WATERS ARE ASSOCIATED WITH THE REMNANTS OF
GASTON. THE CIRCULATION REMAINS POORLY DEFINED AND THE ENVIRONMENT
SURROUNDING THE SYSTEM IS EXPECTED TO BE ONLY MARGINALLY CONDUCIVE
FOR DEVELOPMENT DURING THE NEXT COUPLE OF DAYS. THEREFORE...THERE
IS A LOW CHANCE...20 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL
CYCLONE AGAIN DURING THE NEXT 48 HOURS.

A SMALL LOW PRESSURE AREA LOCATED ABOUT 300 MILES WEST OF THE
NORTHERNMOST CAPE VERDE ISLANDS IS PRODUCING DISORGANIZED SHOWERS
AND THUNDERSTORMS. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN
UNFAVORABLE FOR DEVELOPMENT DURING THE NEXT COUPLE OF DAYS AS THIS
SYSTEM MOVES WESTWARD AT ABOUT 10 MPH. THERE IS A LOW CHANCE...10
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

A LARGE AREA OF CLOUDINESS AND THUNDERSTORMS LOCATED BETWEEN THE
CAPE VERDE ISLANDS AND THE WEST COAST OF AFRICA IS ASSOCIATED WITH
A TROPICAL WAVE. DEVELOPMENT...IF ANY...OF THIS SYSTEM IS EXPECTED
TO BE SLOW TO OCCUR AS IT MOVES WESTWARD AT 10 TO 15 MPH DURING THE
NEXT COUPLE OF DAYS. THERE IS A LOW CHANCE...10 PERCENT...OF THIS
SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BROWN

[WeatherGuesser]

OK, can we call Bones in or is it still on life support?

[Wx_Warrior]

maybe time to look east.

[fasterdisaster]

I'd agree with those chances, but it's important to remember those are only the next 2 days, before he even reaches the central to western Caribbean.

[KWT]

Yeah lower chances aren't surprising, I'm just amazed it took the NHC quite this long to get down to those odds, esp after multiple attempts at trying to hold convection and failing to do so...for the NHC this probably would have to count as a bust given the long tim it spent at 70-80%.

[ColinDelia]

As I stated above, the intensity verification will be very interesting. Very odd to see the LGEM so consistent on ramping this up. The history with the global models is also very interesting with Gaston. This is the storm that not one model saw developing, which is rare in itself. What implications (if any) that has on his future, I'm not sure...

LGEM was the most accurate intensity model the past 3 years but I don't know if it was verified on invests. Is it even applicable?
I don't know the answer to that. Something to look up later. Of course cyclogenesis is difficult for every model and every person!
I would think this is one area there will be a lot of progress in the coming decade.

Gaston has been an interesting one. What precisely did the recon missions find about the environment not being as conducive as expected?
Some difference between the reality and the satellite estimates as far as dry air maybe?

[KWT]

I suspect all that happened is recon confirmed that the global models had the right idea with regards to the background set-up rather then the statistical models that explode Gaston and that combined with recon not finding a LLC probably was enough to justify a large reduction in risk.

[ColinDelia]

GFS, for one, has done a great job with position and development of the upper level high and ULL in its relationship to ex-Gaston.
Not saying anything about any of the other models. Only so many hours in the day and GFS info is more readily available to me.

Of course these models mostly continually approve and we have to all re-learn every year what they can and can't do well

Did the models get lucky on this one so far? Did they not actually have the information necessary to forecast lack of cyclogenesis so far and it just worked out for other reasons? Or were the conditions never going to be all that good at this point and computers saw that better than humans?

[Gustywind]