ATL: DON - Remnant - Discussion

[ROCK]

I don't trust the GFS at all right now. It didn't initialize its vorticity or current precip right at all. The NAM initialized 90L much better tonight imo.

agree

[Jagno]

Does the 0z NAM show a tropical storm heading on a general path towards the LA/TX coastline?

This far out and it's like a roulette wheel and near impossible to say difinetly who will be the recipient or the strength as this would place it in the warmest waters yet. Just keep your eyes on it.

[Rgv20]

Too bad its the third worst tropical model in existence

I don't think the NAM is as bad as it used to be. It handled Tropical Storm Hermine very well last year.j

It sure did but I guess even a broken clock is right twice a day But to be honest it seems this year the global models have been pretty stingy on development in the long range even the crazy one CMC lol

I like the track for 90l on the 0zNAM thru 30-36 hrs other than that I'm gonna disregard the rest of the run.

[South Texas Storms]

It still is firing some nice thunderstorms just south of Cuba right now. I think it is maintaining itself pretty well after being over land some today.

http://weather.msfc.nasa.gov/cgi-bin/post-goes

[fci]

Is this still an Invest?
I don't see it on the S2K map which usually means one of two things:
- a named system or TD
- poof.
I know it has not strengthened so I guess it has been "poofed"?

As of the time I am making this post,even though, 90L is not at the graphic at top of forum, is still active.Is not at the graphic because since 18z of Saturday,no runs of the tropical models have been out and that graphic is automated with what ATCF does.

I think I understand the reasoning but isn't it a problem that if there is an active system it doesn't show on the graphic?

[TwisterFanatic]

700mb Vorticity is pretty strong.




850mb, not so much.

[KWT]

Convection waning this morning, that probably suggests this system is pretty much done...esp given its now close to the NW.Caribbean.

[perk]

Convection waning this morning, that probably suggests this system is pretty much done...esp given its now close to the NW.Caribbean.

I'm gonna give 90L another day, or until it gets in the GOM before i write it off.

[cycloneye]

Discussion by Crown Weather about 90L:

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.

A very disorganized mess of showers and thunderstorms were tracking westward across Hispaniola, eastern Cuba and the southeastern Bahamas. This shower and thunderstorm activity is associated with a tropical wave, designated Invest 90-L by the National Hurricane Center. This tropical wave is expected to continue tracking west-northwestward over the next few days reaching the northwestern Caribbean near the Yucatan Peninsula by Tuesday afternoon and evening and then the southern Gulf of Mexico during the day Wednesday.

The chances of development are nil today due to the interaction with Hispaniola and Cuba. Conditions may become more favorable from later Tuesday into Wednesday as this tropical wave reaches the northwestern Caribbean and the southern Gulf of Mexico where the upper level conditions are more favorable. In addition, another reason why this wave has not developed is due to the fast forward speed of 20 mph. This fast forward speed is disrupting convection where the best convergence is outrunning any convection that is developing. This tropical wave is expected to slow down considerably in forward speed during Tuesday and Wednesday as it reaches the northwestern Caribbean and the southern Gulf of Mexico.

I think the combination of more favorable environmental conditions and the slow-down in forward speed will cause an increase in convergence and concentrated convection and we will need to keep an eye on this system for possible development starting late on Tuesday and continuing through Wednesday as it tracks from the northwestern Caribbean to the southern Gulf of Mexico.

It should be noted that Invest 90-L is receiving very little love from any of the global model guidance like the European and GFS models. The NAM model, however, is forecasting that Invest 90-L will start organizing during the day Tuesday and will strengthen into a possible tropical depression or tropical storm as we get into late Wednesday and Thursday as it reaches the south-central Gulf of Mexico. The NOGAPS model also hints at some weak development on Friday just before it comes ashore in south Texas.

This tropical wave will bring heavy rain and gusty winds to much of Hispaniola, Cuba and the central and southeastern Bahamas from today through Tuesday. This heavy rainfall and gusty winds will spread into the Cayman Islands and Yucatan Peninsula during the day Tuesday and continue into Wednesday.

My opinion is that I expect no development from today through Tuesday. After that, I think this tropical wave needs careful monitoring as it reaches the southern Gulf of Mexico on Wednesday and Thursday where the upper level conditions will become more favorable for development. Later this week, the upper level steering currents are such that Invest 90-L, whether it develops or not, will track onshore onto the central or southern Texas coast on Friday into Saturday. At the very least, it will bring a considerable increase in rainfall late this week to central and southern Texas, however, this system will need to be watched closely in case it develops into a tropical storm.

[KWT]

That discussion sounds fair enough, I didn't think it needed watching but to be honest I think the odds are now on the side of non-development given if anything its weakening again over the NW Caribbean.

Still its true I spose, its not quite totally finished.

[cycloneye]

Down to 0%.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT MON JUL 25 2011

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

DISORGANIZED SHOWERS AND A FEW THUNDERSTORMS OVER CUBA AND THE
ADJACENT WATERS ARE ASSOCIATED WITH A TROPICAL WAVE. SIGNIFICANT
DEVELOPMENT OF THIS SYSTEM IS NOT EXPECTED DURING THE NEXT COUPLE
OF DAYS AS IT MOVES GENERALLY WESTWARD NEAR 20 MPH AND INTERACTS
WITH LAND. THIS SYSTEM HAS A LOW CHANCE...NEAR 0 PERCENT...OF
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

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

$$
FORECASTER PASCH/ROBERTS

[NDG]

Hmm, I don't know why the NHC circled the NW Caribbean, the vorticity looks like it is still over or near eastern Cuba.

[NDG]

BTW, just looked at last night's model runs, forecasted upper level conditions don't look that atractive any more this week in the GOM, upper level strong easterly shear due to the death ridge seem to stay place the whole week. Might be the reason why the NHC brought it down to 0% besides continuing no global model support. Next! lol

[perk]

BTW, just looked at last night's model runs, forecasted upper level conditions don't look that atractive any more this week in the GOM, upper level strong easterly shear due to the death ridge seem to stay place the whole week. Might be the reason why the NHC brought it down to 0% besides continuing no global model support. Next! lol

I think the discussion from crownweather is dead on. They seem to think that conditions in the GOM will favor further development.

[Aric Dunn]

like with anything in the tropics you cant say never.... over the next couples days it will be slowing down and could give it a chance to maintain convection.

[Aric Dunn]

Speaking of which. I see a lot more curvature to the low level flow this morning. north west of Jamaica and just south of eastern cuba. in the vicinity of that recent blob of convection.

[NDG]

BTW, just looked at last night's model runs, forecasted upper level conditions don't look that atractive any more this week in the GOM, upper level strong easterly shear due to the death ridge seem to stay place the whole week. Might be the reason why the NHC brought it down to 0% besides continuing no global model support. Next! lol

I think the discussion from crownweather is dead on. They seem to think that conditions in the GOM will favor further development.

I wonder what makes Rob think that or what model is he looking at that shows good upper level conditions, I don't see that.
The ECMWF a couple of nights ago showed a pocket of better UL conditions moving along with the wave but it does not show that any more in its last two runs.

[Aric Dunn]

Speaking of which. I see a lot more curvature to the low level flow this morning. north west of Jamaica and just south of eastern cuba. in the vicinity of that recent blob of convection.

[NDG]

I would put your circle just a little more to the east between Jamaica and Santiago de Cuba. Half of the vorticity is over land, IMO.

[Aric Dunn]

:uarrow: I would put your circle just a little more to the east between Jamaica and Santiago de Cuba. Half of the vorticity is over land, IMO.

its a generalization.. just the area where the flow changes from SE to NE. its a not a low level center. just the wave axis.