ATL: BERTHA - Post-Tropical - Discussion

[gatorcane]

Latest saved vis loop...structure looks good but we have a naked swirl alert..some convection on the south side of the wave...gaining a little bit of latitude:

[TheStormExpert]

Michael Lowry on TWC just recently said that the window of opportunity for this to develop is quickly closing. He also showed a WV imagery of dry air quickly engulfing the surrounding area of 93L.

I think I smell Bones appearance coming soon!

[cycloneye]

Levi Cowan made a video about 93L.

http://www.tropicaltidbits.com/blog/201 ... erto-rico/

[Alyono]

Invest 93L shouldn't amount to much more than some sporadic showers and gusty winds for the Lesser Antilles. It was pretty much over when easterly shear allowed dry air into the circulation. Because this isn't an intensifying cyclone with active convection, it won't be able to split the upper-level trough waiting for it near the islands like the GFS suggested days ago, and it will likely be sheared to death (what remains of it, anyways).

Looking ahead, I don't see any reason to suggest things are going to improve in the Atlantic. Shear may have lowered in the central and eastern Atlantic, but the dry air and SAL are overwhelming, even despite a cool Gulf of Guinea and wet Sahel (fueling stronger-than-average waves). The MJO should lose amplitude as it heads towards our basin early next month.

For the thousandth time, cold water in the IO favors WEAKER systems. Multiple mets have stated this previously here

I didn't mention anything about the Indian Ocean, I mentioned the Gulf of Guinea (south of Africa) and the Sahel region...

But since we're on the subject, no, a cold Indian Ocean does not favor weaker systems. For the thousandth time, here is a sea surface temperature composite of the top ten ACE years in the Atlantic:



Average if not slightly cooler than average.

But if you want to continue to ignore the data, read pages 9 and 10 from the CPC's climate perspective on the 2011 Atlantic hurricane season, with contributions from the hurricane specialists at the NHC.

This will be further investigated

[TheStormExpert]

Latest saved vis loop...structure looks good but we have a naked swirl alert..some convection on the south side of the wave...gaining a little bit of latitude:

http://i61.tinypic.com/25zte2g.jpg

There must be some Northerly Shear where the LLC is located cause whatever t-storm activity is there is staying shoved to the south it looks like.

[Hurricane Alexis]

It kinda looks like the swirl is outrunning the convection.

[cycloneye]

Note=Follow Gonzo's flight to Barbados here

[northjaxpro]

Michael Lowry on TWC just recently said that the window of opportunity for this to develop is quickly closing. He also showed a WV imagery of dry air quickly engulfing the surrounding area of 93L.

I think I smell Bones appearance coming soon!

Yeah, the dry air is definitely winning out at this current time. Conditions just remain too hostile for tropical cyclone formation out there in the MDR as the SAL is just too overwhelming out there. EURO apparently was right all along with never really developing the system going back to its runs late Sunday and this past Monday.

As for Bones coming in making his final proclamation, well, not yet. However, if current trends continue, he could be coming in by sometime within the next 24 hours as I feel 93L will become an open wave well before approaching the islands. We will see if 93L has some fight left.

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The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster . It is NOT endorsed by storm2k.org. Pleas refer to the latest products from the National Hurricane Center.

[tropicwatch]

Shower activity is on the increase if it keeps going might have a chance still. I know that is a big if

[gatorcane]

Tropical cyclone formation probability for the next 24 hours is actually higher for the wave behind 93L, which has some good spin by the way.

Topic for this wave behind 93L here:
viewtopic.php?f=31&t=116532

[Blown Away]

Some deep reds forming near the LLC...

[Sanibel]

Same as 02L. Dissipating shear from the North.

[colbroe]

Looks like 93l is making a comeback convection building around the center of circulation ,best it has looked since it was declared an invest . Waters closer to the islands are a little warmer ,my fare this thing might explode as it nears the islands ,any thoughts.

[Alyono]

Invest 93L shouldn't amount to much more than some sporadic showers and gusty winds for the Lesser Antilles. It was pretty much over when easterly shear allowed dry air into the circulation. Because this isn't an intensifying cyclone with active convection, it won't be able to split the upper-level trough waiting for it near the islands like the GFS suggested days ago, and it will likely be sheared to death (what remains of it, anyways).

Looking ahead, I don't see any reason to suggest things are going to improve in the Atlantic. Shear may have lowered in the central and eastern Atlantic, but the dry air and SAL are overwhelming, even despite a cool Gulf of Guinea and wet Sahel (fueling stronger-than-average waves). The MJO should lose amplitude as it heads towards our basin early next month.

For the thousandth time, cold water in the IO favors WEAKER systems. Multiple mets have stated this previously here

I didn't mention anything about the Indian Ocean, I mentioned the Gulf of Guinea (south of Africa) and the Sahel region...

But since we're on the subject, no, a cold Indian Ocean does not favor weaker systems. For the thousandth time, here is a sea surface temperature composite of the top ten ACE years in the Atlantic:



Average if not slightly cooler than average.

But if you want to continue to ignore the data, read pages 9 and 10 from the CPC's climate perspective on the 2011 Atlantic hurricane season, with contributions from the hurricane specialists at the NHC.

Had a chance to look through some data with others at work

http://www.jamstec.go.jp/frcgc/research ... onthly.txt

2005…IOD small negative, but most storms developed west of 55 (28/15/7) (Note TNA was well above normal and this was the main influence)


1995…IOD was positive (19/11/5)…verified


2004…IOD was positive (15/9/6)…verified


1950…IOD averaged positive (13/11/8)…verified…higher number of hurricanes/majors


1961…IOD averaged positive (11/8/7)…verified…high number of hurricanes/majors



1955…IOD averaged negative (12/9/6)…most development west of 50


1998…IOD averaged negative (14/10/3) (Note TNA was +0.6C above normal…this was the main influence)



1999…IOD averaged positive (12/8/5)…verified…high number of hurricanes/majors


2003…IOD averaged positive (16/7/3)…verified


1964…IOD averaged negative (12/6/6)…most development west of 55

warmer western Indian Ocean seems to be more favorable. However, I will do more extensive research on this matter tomorrow morning, with far more quantification

[cycloneye]

To have a better discussion apart from 93L about what is going on in N Atlantic,a new thread about the multidecade active period has been made so the discussions can be posted there instead of the 93L thread.Go here.

[JonathanBelles]

New Post: 93L Fights Back Against Dry Air: Will It Win? http://wp.me/p1xnuB-fX

[SFLcane]

Touch battle but some storms developing.

[NDG]

I was just thinking that as 93L approaches the TUTT it might help it fire up some convection, good for the Islands rainwise.

[cycloneye]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT WED JUL 30 2014

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

Shower activity associated with a well-defined low pressure system
located about 900 miles east of the southern Windward Islands has
changed little over the past several hours. However, environmental
conditions are marginally conducive for the development of this
system into a tropical depression during the next couple of days.
Interests in the Lesser Antilles should monitor the progress of this
system as it moves west-northwestward near 15 mph.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 5 days...medium...50 percent.

$$
Forecaster Stewart

[northjaxpro]

Down to 50% now by NHC. Also, NHC now going with the dreaded "marginally conducive" terminology for development, which is definitely not a good sign for 93L as this is only confirming the hostile conditions maintaining out there in the MDR.

93L currently gasping for air.

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Personal Forecast Disclaimer:

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the National Hurricne Center.