ATL: EDOUARD - Post-Tropical - Discussion

[wxman57]

Relying on GFS projections of development may not be a good idea. I went back and checked its forecast valid for 12Z today (an hour ago) from last Friday:

Friday, Sept. 5: 988 mb storm west of Cape Verde Islands
Saturday, Sept. 6: 980 mb storm west of Cape Verde Islands
Sunday, Sept. 7th: 1009 mb low
Monday, Sept. 8th: 1005 mb low
Tuesday, Sept. 9th: 1009 mb low

I don't see a hurricane out there today (forecasts from Friday/Saturday), or even a closed low center (Sun-Tue forecasts). It's just an average tropical wave. And if you check out the TPW loop (http://tropic.ssec.wisc.edu/real-time/m ... /main.html) you'll see that rotation is decreasing, not increasing. It still may develop in 2-3 days, but I don't think development is a given by any means.

[tolakram]

Not many frames available today but it does appear there may still be an elongated low level circulation.

http://rammb.cira.colostate.edu/ramsdis/online/loop.asp?data_folder=tropical/tropical_ge_4km_visir2_floater_2&width=640&height=480&number_of_images_to_display=3

I'm going to guess a mention of "showing signs of organization", but we'll see.

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 and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[cycloneye]

Shower activity associated with a broad area of low pressure located
about 600 miles west of the Cape Verde Islands remains disorganized.
While tropical cyclone formation is not anticipated today,
environmental conditions could become somewhat more favorable for
development by later in the week while the low moves toward the
west-northwest and northwest at about 15 mph over the open Atlantic.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...high...70 percent.

[Hammy]

Do my eyes deceive me? Is something actually beginning to organize in the MDR this year?

[Gustywind]

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT WED SEP 10 2014


A TROPICAL WAVE IN THE E ATLANTIC EXTENDS FROM 9N33W TO 19N32W
MOVING W AT 10-15 KT. A SW-NE ELONGATED 1009 MB SURFACE LOW IS
CENTERED ALONG THE WAVE AXIS NEAR 13N32W. MOST CONVECTION IS
OCCURRING ALONG THE SW-NE ORIENTED LOW PRESSURE AXIS WITH
SCATTERED TO MODERATE CONVECTION FROM 11N-18N BETWEEN 30W-37W

[Hyperstorm]

Do my eyes deceive me? Is something actually beginning to organize in the MDR this year?

Yes, it is.

I see a new area of convection developing near 14 N and 34 W. I think the center is trying to consolidate just to the east of there. I think what's different with this disturbance versus others recently in this area is the large amplitude of moisture to the northeast. I see it as a guard that's keeping it from dissolving like previous ones. Also, having new convection developing on top of already decent convection signals persistence.

If we can get a tighter LLC...

[Hyperstorm]

While the system east of Florida is getting most of the focus tonight, the tropical wave in the eastern Atlantic seems to be slowly coming together. A burst of heavy-duty thunderstorms has occurred in a very compact area indicating some good tightening going on. Outflow also seems to be expanding to the north and west. If convection persists through tonight, I would not be surprised if the system is classified within 24 hours.

Watching for persistence...

[Hammy]

This system feels like it's been out there forever now, could be developing at the surface, and hopefully it'll get a direct ASCAT pass this time instead of it missing to one side or the other.

[northjaxpro]

Do my eyes deceive me? Is something actually beginning to organize in the MDR this year?

LOL.. Yeah Hammy it is at this point to nearly incredulous how these waves out in the MDR has gone poof this season with the hostile conditions. However, I agree with you and your eyes are not deceiving you this time. 91L seems to have done a nice job of fending off the hostile conditions.. ie. mid level dry air.. and now I must say this is the best looking wave we have seen out there to this point this season.

If the trends continue and convection persists, and the system already has a good outflow and moisture envelope, we may see a classification of this system to a TD in the near term.

[floridasun78]

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT WED SEP 10 2014

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

1. Satellite images indicate that the shower activity associated
with a broad area of low pressure centered about 650 miles west of
the Cape Verde Islands has increased and become a little better
organized this evening. This system is now moving toward an area
more favorable for development, and a tropical depression could form
during the next day or two while the low moves toward the
west-northwest and northwest at about 15 mph over the open Atlantic.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...high...70 percent.

[Hurricaneman]

anyone notice the blob next to 91L as it has intense convection. Could this add more moisture to 91L

[Hammy]

anyone notice the blob next to 91L as it has intense convection. Could this add more moisture to 91L

It could at least ward off drier air from the SAL.


http://tinyurl.com/kft96tu

I'd say personally this looks like it now qualifies as a tropical depression.

[bahamaswx]

anyone notice the blob next to 91L as it has intense convection. Could this add more moisture to 91L

It could at least ward off drier air from the SAL.

[img]http://oi61.tinypic.com/16bxzl5.jpg[img]
http://tinyurl.com/kft96tu

I'd say personally this looks like it now qualifies as a tropical depression.

Persistent convection and a LLCC? Check.

[Extratropical94]

From tonight:

Shower activity associated with a broad area of low pressure
centered about 750 miles west of the Cape Verde Islands continues
to show signs of organization. Conditions are expected to become
more favorable for development, and a tropical depression could form
during the next day or two while the low moves toward the west-
northwest and northwest at about 15 mph over the open Atlantic.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 5 days...high...80 percent.

[Rail Dawg]

I'd like to see a forum feature where we can log in our predictions and then have a running track record all can see.

We always had a running bet in the office.

This system is developing and I think we'll get a hurricane out of it fairly quickly.

[tolakram]

Live visible loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20NHE&lat=19&lon=-39&info=vis&zoom=1&width=1024&height=768&type=Animation&quality=92&palette=ir1.pal&numframes=5

12:15Z

[galaxy401]

Code red now.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT THU SEP 11 2014

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

1. Shower activity associated with a broad area of low pressure
centered about 750 miles west of the Cape Verde Islands has become
better organized during the past several hours. If current trends
continue, a tropical depression could form later today or tonight
while the low moves toward the west-northwest and northwest at about
15 mph over the open Atlantic.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...90 percent.

[wxman57]

Looks like a TD to me now. NHC should upgrade in a few hours. No threat to the Caribbean or Bermuda.

[tropicwatch]

NHC will be initiating advisories at 11 a.m. EDT on Tropical Depression Six, located over the eastern Atlantic Ocean.
http://www.hurricanes.gov

[TropicalAnalystwx13]

TROPICAL DEPRESSION SIX DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL062014
1100 AM EDT THU SEP 11 2014

Satellite imagery and a recent ASCAT-B overpass indicate that the
low pressure area over the eastern Atlantic has a well-defined
circulation and organized convective banding near the center. Thus,
advisories are being initiated on Tropical Depression Six. The
initial intensity is set at 30 kt based on the scatterometer data
and the satellite intensity estimate from TAFB.

The initial motion is 310/12. A low-/mid-level ridge north of the
cyclone should steer it generally west-northwestward to
northwestward for the next 3-4 days. After that, the track
guidance forecasts the system to turn generally northward between
the ridge and a large mid-/upper-level low south of Bermuda. There
is a fair amount of spread in the guidance on where this turn should
occur, with the extremes being the Canadian model on the east near
45W and the ECMWF model on the west near 55W. The official forecast
lies close to the model consensus in expecting a more northerly
motion between 51W-53W. The forecast track keeps the cyclone well
away from land for the next 5 days.

The depression is currently in an environment of light vertical
wind shear. The large-scale models forecast some increase
in southerly shear after 24 hours, which should persist through the
end of the forecast period. Despite the shear, the intensity
guidance forecasts slow but steady strengthening. The official
forecast follows this scenario and is a blend of the SHIPS model and
the intensity consensus.

FORECAST POSITIONS AND MAX WINDS

INIT 11/1500Z 16.2N 37.1W 30 KT 35 MPH
12H 12/0000Z 17.1N 38.5W 35 KT 40 MPH
24H 12/1200Z 18.2N 40.7W 40 KT 45 MPH
36H 13/0000Z 19.3N 42.9W 45 KT 50 MPH
48H 13/1200Z 20.5N 44.9W 50 KT 60 MPH
72H 14/1200Z 23.5N 48.5W 55 KT 65 MPH
96H 15/1200Z 26.5N 51.5W 60 KT 70 MPH
120H 16/1200Z 29.0N 53.0W 70 KT 80 MPH

$$
Forecaster Beven