ATL: INVEST 90L - Discussion

[cycloneye]

AL, 90, 2014090306, , BEST, 0, 149N, 121W, 15, 1010, LO, 0, , 0, 0, 0, 0, 1012, 200, 80, 0, 0,
AL, 90, 2014090312, , BEST, 0, 146N, 136W, 15, 1010, LO, 0, , 0, 0, 0, 0, 1012, 200, 80, 0, 0,
AL, 90, 2014090318, , BEST, 0, 142N, 151W, 15, 1010, LO, 0, , 0, 0, 0, 0, 1012, 200, 80, 0, 0,
AL, 90, 2014090400, , BEST, 0, 136N, 165W, 20, 1009, LO, 0, , 0, 0, 0, 0, 1012, 200, 70, 0, 0,
AL, 90, 2014090406, , BEST, 0, 128N, 178W, 20, 1009, LO, 34, NEQ, 0, 0, 0, 0, 1012, 200, 70, 0, 0, L, 0, ,



Thread at Talking Tropics forum that was the topic for this area.

viewtopic.php?f=31&t=116685&start=0

[ouragans]

Up to 40%

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT THU SEP 4 2014

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

1. A tropical wave, accompanied by a broad low pressure system, has
emerged off the coast of Africa a few hundred miles east-southeast
of the Cape Verde Islands. Environmental conditions are expected to
be conducive for gradual development of this disturbance through
early next week while it moves westward at about 15 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...40 percent.

Forecaster Stewart

[Gustywind]

What is the future of this twave with all that dry air north of it? That should be a difficult trip but as we're approaching the peak we must have to keep an eye on... Note that this is a good news that 90L have not already poofed .
Time will tell.
http://tropic.ssec.wisc.edu/real-time/sal/splitE.jpg

[Gustywind]

From the Weather Channel

Stu Ostro, Michael Lowry, Dr. Greg Postel Published: Sep 4, 2014, 5:46 AM EDT weather.com


ATLANTIC

http://www.weather.com/news/tropical-up ... n-20140513

A strong tropical wave with a circular appearance already is coming off Africa. Models are not bullish on its development potential, while also not turning it out to sea anytime soon either. There's an even stronger "African easterly wave" that'll be heading into the Atlantic in a few days. It too will have various atmospheric adversaries to overcome in order to survive all the way across, but the ultimate outcome is a long way off and yet t.b.d.

[Gustywind]

Very interresting discussion from Jeff Masters

http://www.wunderground.com/blog/JeffMa ... rynum=2784

New African tropical wave this weekend may develop
A tropical wave is expected to come off the coast of Africa on Thursday and move to the west at about 15 mph. This wave will be capable of bringing heavy rain and strong winds to the Cape Verde Islands on Friday and Saturday. Two of our three reliable computer models for predicting tropical storm formation show development by Sunday of the wave, and in their 8 am EDT Wednesday Tropical Weather Outlook, NHC gave the system 2-day and 5-day odd of development odds of 0% and 30%, respectively. The Wednesday morning runs of the GFS and European ensemble models favored the storm taking a more west-northwesterly track into the open ocean next week, with a low long-range threat to the Lesser Antilles Islands indicated. However, it is too early to be confident that the storm will miss the islands, as the long-range tracks have shifted closer to the Lesser Antilles since their runs on Tuesday. The Atlantic is expected to be dominated by dry, sinking air next week, due to the phase of the Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, so I expect that any tropical waves crossing from Africa towards the Lesser Antilles will struggle to develop.

Jeff Masters

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT THU SEP 4 2014

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

1. A tropical wave, accompanied by a broad low pressure system, is
located a few hundred miles east-southeast of the Cape Verde
Islands. Environmental conditions are expected to be conducive for
some development of this disturbance through early next week while
it moves westward at about 15 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...40 percent.

Forecaster Pasch

[northjaxpro]

Of course, the saga of the 2014 North Atlantic Hurricane season continues. Will the ambundant dry and stable air destroy another in a series of these African waves? Or will 90L somehow survive to last in the next few days?

[cycloneye]

8 AM TWD:

A TROPICAL WAVE IS OVER THE EASTERN ATLANTIC WITH AXIS NEAR
19N41W TO 05N44W MOVING W AT 15-20 KT. SSMI TOTAL PRECIPITABLE
WATER VAPOR IMAGERY SHOWS A LARGE MOIST AREA IN THE VICINITY OF
THIS WAVE. ISOLATED MODERATE CONVECTION REMAINS W OF THE WAVE
AXIS E OF 40W...BETWEEN 11-15N.

[tolakram]

Mid level water vapor looks moist enough, certainly a lot better than earlier in the year.



source: http://tropic.ssec.wisc.edu/real-time/salmain.php?&prod=wvmid&time=

[TheStormExpert]

Yeah once you head west of 50w then moisture increases.

[tolakram]

live visible loop: http://rammb.cira.colostate.edu/ramsdis/online/loop_meteosat.asp?data_folder=tropical/tropical_met_14km_visir2&width=640&height=480&number_of_images_to_display=24

[Alyono]

convection collapsing

a decent chance of developing, but I wouldn't expect anything beyond a moderate TS through 7 days

[gatorcane]

90L floater IR saved loop. The big convection burst we were watching from last night did collapse, but the structure is looking good, and there still is convection hanging on:

[meriland23]

Why is it collapsing?

[gatorcane]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT THU SEP 4 2014

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

1. A tropical wave, accompanied by a broad low pressure system, is
located a few hundred miles east-southeast of the Cape Verde
Islands. Environmental conditions are expected to be conducive for
some development of this disturbance through early next week while
it moves westward at about 15 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...40 percent.

Forecaster Pasch

[Sanibel]

Few storms seem to be taking this year. The GOM seems to be ready now but there are no disturbances entering it.

[SFLcane]

Why is it collapsing?

Likely the same issue most systems this year have had. Dry sinking airmass ahead will most likely keep this from developing anytime soon. Wouldn't be surprised if this a naked convection free swirl in a few days.

[USTropics]

Cooler then normal SSTs plus dry air is what caused the convection to collapse. It'll take some time to adjust to its new environment.

[YoshiMike]

what does sst mean?

[crownweather]

SST=Sea Surface temperatures.