Ex Invest 99L in Western Atlantic

[stevetampa33614]

Here is a visible loop showing our our invest has made that west turn as forecasted and is racing west at 15-20mph...towards warmer SSTs:

http://www.ssd.noaa.gov/goes/east/tatl/loop-vis.html

You can see there is a chance it may start to move south of 270 or between W to WSW over the new couple of days and the forecast reasoning for 98L to stay on a west track for quite a while

I checked the wind shear tendency and it looks like some only marginally favorable upper-level winds are out ahead of 98L so slow and steady development is possible.

Please correct me if im wrong, but if it stays really weak than its going to keep heading pretty much due west. Correct?

[gatorcane]

I have to say I'm rather surprised with the lack of interest in this system. I do anticipate it will gather considerably more interest within the next couple of days especially over the weekend when we should see increased organization and a west to westsouthwest

In fact TAFB is even showing a WSW movement from 98Ls current position. We certainly need to watch 98L IMHO.

[Ed Mahmoud]

Please correct me if im wrong, but if it stays really weak than its going to keep heading pretty much due west. Correct?

Assuming low level steering is its usual East to West direction.

If this stays below about 20ºN, it should generally head West.

[KWT]

This may yet do something past 40W if it can survive indeed the longerit keeps the circulation the better the odds but even then at 17-18N chances are that it will recurve way before it becomes any real threat to any islands with maybe the only threat being to Bermuda if it does stay due west for a little while and stays weak.

[gatorcane]

KWT what do you think of how far south the vortex is in the TAFB estimate from above (and my analysis that I presented in a few posts above)?

[KWT]

To be honest I'm not sure, this probably will bend back due west maybe there could even be some slightly south of west motion for a short while but I think that estimate may be a touch too far to the south, esp if it does go on to do something, the only way its right IMO is if this remians a weak wave feature.

[Gustywind]

000
AXNT20 KNHC 311722
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT THU JUL 31 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1715 UTC.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS W OF THE CAPE VERDE ISLANDS
ALONG 27W SOUTH OF 22N. A 1009 MB LOW PRESSURE CENTER IS ALONG
THE WAVE AXIS NEAR 18N26W. SCATTERED SHOWERS ARE WITHIN 200 NM
EITHER SIDE OF THE WAVE AXIS. CONDITIONS ARE NOT CONDUCIVE FOR
SIGNIFICANT DEVELOPMENT DURING THE NEXT COUPLE OF DAYS DUE
PRIMARILY TO COOLER SEA SURFACE TEMPERATURES.
Troubles for this perturbed area, seems afterwards that cool sst's are inhibiting all the latests systems near CV islands for two weeks right now, (since Dolly) let's enjoy maybe once one quiet week before another round of surprises in store. So time call for a moment, let's appreciate the calm before the possibles storms of August my friends....

[gatorcane]

To be honest I'm not sure, this probably will bend back due west maybe there could even be some slightly south of west motion for a short while but I think that estimate may be a touch too far to the south, esp if it does go on to do something, the only way its right IMO is if this remians a weak wave feature.

Latest Vis loops show it already is making a just south of west turn. I estimate 98L is moving 265 now. Warmer waters are ahead for it.

Again I do think 98L or some variation of it is heading towards the Northern Leewards and will either get close (just to the NE) or pass through the northern leewards.

http://www.ssd.noaa.gov/goes/east/catl/loop-vis.html

[KWT]

Well its really hard to tell its movement using that given how far zoomed out it is, would want to see a much closer image of the system. However what is obvious is that it does have some good cyclonic turning to it.

[gatorcane]

It's currently moving over SSTs around 77F, just 1 degree below the required 78F needed for tropical cyclone development.

If you click on the SST box in the link I provided above, you can see that within about 36 hours it will be in 78-79F temps, the minimum to support tropical cyclone development. Then once it passed 40W it will be in 80-81F temps which is where some real convection should start to show up.

But it won't reach the 80-81F SSTs for about 2-3 days, hence the reason why the TWO is not indicating any development in the next 48 hours but beyond 48 hours things may change.

[cycloneye]

Invest 98L has been deactivated and is anymore on NRL site.It means this thread will return to Talking Tropics forum.If they tag it again as 98L,the thread will return to active storms forum.


NHC
invest_DEACTIVATE_al982008.ren
FSTDA
R
U
040
010
0000
200807311215
NONE
NOTIFY=ATRP
END
INVEST, AL, L, , , , , 98, 2008, DB, O, 2008073000, 9999999999, , , , , , METWATCH, , AL982008
AL, 98, 2008072918, , BEST, 0, 137N, 172W, 20, 1008, DB, 0, , 0, 0, 0, 0,
AL, 98, 2008073000, , BEST, 0, 144N, 179W, 20, 1008, DB, 0, , 0, 0, 0, 0, 850, 0, 0, 0, 0,
AL, 98, 2008073006, , BEST, 0, 146N, 189W, 20, 1007, DB, 0, , 0, 0, 0, 0, 1009, 150, 0, 0, 0, L, 0, , 0, 0, INVEST, D,
AL, 98, 2008073012, , BEST, 0, 154N, 199W, 25, 1008, DB, 0, , 0, 0, 0, 0, 1011, 150, 20, 0, 0, L, 0, , 0, 0, INVEST, D,
AL, 98, 2008073018, , BEST, 0, 165N, 215W, 25, 1008, DB, 0, , 0, 0, 0, 0, 1011, 150, 20, 0, 0, L, 0, , 0, 0, INVEST, D,
AL, 98, 2008073100, , BEST, 0, 169N, 232W, 25, 1007, DB, 0, , 0, 0, 0, 0, 1011, 150, 20, 0, 0, L, 0, , 0, 0, INVEST, D,
AL, 98, 2008073106, , BEST, 0, 176N, 250W, 25, 1007, DB, 34, NEQ, 0, 0, 0, 0, 1011, 150, 20, 0, 0,

[SapphireSea]

The system does not look very bad today, SSTs should be getting better as it heads W (275-280 IMO), it will soon enter into an area of mild westerly shear, and down the road into moderate to strong westerly shear if it does not change course or the shear diminishes. I believe it's chances of development in the short term are much better now. If the development comes to pass it will likely only be a maritime hazard if you extrapolate the current movement and steering patterns, this of course is speculation.

[HURAKAN]

[stevetampa33614]

So basically we will be watching this for 10 days as it slugs its way to the antilles.

Not unlike, Dolly/94L (was it 94L?Or 96?)

[gatorcane]

Impressive visible signature this afternoon as you can see ex-98L on the far right-hand side of the picture as it heads due West.

[Honeyko]

It's currently moving over SSTs around 77F, just 1 degree below the required 78F needed for tropical cyclone development.

It's not the SST that matters so much as the lapse-rate in the atmosphere above the water. Given the bottom of the sunspot cycle, the earth's atmosphere is thinner right now. This tends to promote convection due to lack of capping layers.

[Blown Away]

I have to say I'm rather surprised with the lack of interest in this system. I do anticipate it will gather considerably more interest within the next couple of days especially over the weekend when we should see increased organization and a west to westsouthwest
In fact TAFB is even showing a WSW movement from 98Ls current position. We certainly need to watch 98L IMHO.

You make some good points. If the circulation maintains and based on the TAFB ex 98L will be near 16N/50W in 3 days, there will be warm SST's and no given of a recurve at that spot. 16N/50W is a historic Islands/CONUS striking point area for many hurricanes.

[gatorcane]

If you look at all hurricanes impacting the US and Caribbean islands passing within 65NM of 16N, 50W for the month of August, you will find the following

-3 landfalling CONUS systems, 2 of which hit the Palm Beach area of Florida on the East Coast of Florida (including Frances in 2004)
-4 passed through the Leeward islands north of 16N.

But Note: all of these systems become tropical storms or depressions much farther east of those coordinates generally now further west than 35W

and...all of these systems formed at or SOUTH of 15N. Note ex-98L is a several degrees in lattitude north of 15N so based on climatology ex-98L should not be a hurricane threat to the Leewards or US

[fasterdisaster]

I really don't see why they took its invest status away. Granted, 24 hours ago I think it was a depression and now it probably isn't, but it has more than enough organization to still be an invest.

[alan1961]

another thing with ex 98L is that the blow up from the ITCZ below it might feed the circulation some much needed moisture.