ATL: KARL - Post-Tropical - Discussion

[Alyono]

EC looks like a weak TD or a remnant low passing north of the Caribbean in 96 hours

[Alyono]

FWIW, hot garbage EC is weak and the farthest east

[GCANE]

Looks like shear is letting up. Getting a cell very close to the CoC.

http://www.ssd.noaa.gov/PS/TROP/floater ... -long.html

[GCANE]

[GCANE]

[cycloneye]

TROPICAL STORM KARL DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL AL122016
500 AM AST SAT SEP 17 2016

Karl is maintaining the status quo with its center at least 120
n mi to the southwest of the deep convection. Since the ASCAT pass
from last evening showed a sizable area of 35-40 kt winds, and the
Dvorak estimates have been steady, the initial intensity remains 40
kt. Karl is located just to the south of an upper-level low, and
the resultant westerly shear should gradually relax and change
direction during the next few days once Karl moves away from this
feature. Sea surface temperatures will be steadily increasing along
Karl's forecast path, and mid-tropospheric moisture may begin to
increase after 48 hours. Therefore, the NHC intensity forecast
continues to call for little change in intensity during the next 48
hours, followed by steady strengthening from day 3 to day 5. This
forecast closely follows an average of the SHIPS and LGEM models
and still allows for the possibility of Karl becoming a hurricane
by day 5.

There is no doubt that the center of Karl has been losing latitude
during the past 6-12 hours, and the initial motion estimate is
265/12 kt. A strengthening low- to mid-level ridge over the central
Atlantic is expected to continue pushing Karl south of due west
during the next 36 hours. After that time, Karl will begin to
approach a weakness in the ridge located over the western Atlantic,
and the tropical cyclone is forecast to move west-northwestward on
days 3-5 well to the northeast of the Leeward Islands. Although
there is some uncertainty on how far south Karl will get before it
turns west-northwestward, the spread among the track models is
actually quite small. The updated NHC track forecast essentially
lies along the TVCN multi-model consensus line, which ends up being
a little south and west of the previous forecast.

FORECAST POSITIONS AND MAX WINDS

INIT 17/0900Z 18.2N 38.2W 40 KT 45 MPH
12H 17/1800Z 18.1N 40.1W 35 KT 40 MPH
24H 18/0600Z 17.9N 42.8W 35 KT 40 MPH
36H 18/1800Z 17.6N 45.4W 40 KT 45 MPH
48H 19/0600Z 17.8N 47.9W 40 KT 45 MPH
72H 20/0600Z 19.4N 53.1W 50 KT 60 MPH
96H 21/0600Z 22.0N 58.5W 60 KT 70 MPH
120H 22/0600Z 24.5N 63.0W 70 KT 80 MPH

$$
Forecaster Berg

[SFLcane]

EC looks like a weak TD or a remnant low passing north of the Caribbean in 96 hours

European has woken up to the hostile tropical atlantic.

[Emmett_Brown]

Motion slightly south of due west this morning, so the southerly component of early track forecasts seems to be happening a bit for now. 6z GFS showing a weaker trough at 168 hrs over the Hudson Bay than on the 0z run. Causes a weak Karl to meander off the SE US coast before ultimately recurving on the next trough at 234 hours. Bermuda is more at risk on these latest model runs.

[Alyono]

This may be in even worse shape than Julia. The circulation is not as defined as is Julia's and it is getting sheared just as badly. There is a chance this opens up within the next 24 hours

[abajan]

This may be in even worse shape than Julia. The circulation is not as defined as is Julia's and it is getting sheared just as badly. There is a chance this opens up within the next 24 hours

I don't think that's going to happen, as it's heading into a progressively more favorable environment.

[Kazmit]

Not sure what the CMC was thinking here, but it looks to me like a worst-case scenario. The eye goes right over Bermuda and then hits them with the back eyewall. Seems like a 940 mbar hurricane is quite unlikely, but Bermuda still needs to watch out for this one.

[Alyono]

This may be in even worse shape than Julia. The circulation is not as defined as is Julia's and it is getting sheared just as badly. There is a chance this opens up within the next 24 hours

I don't think that's going to happen, as it's heading into a progressively more favorable environment.

Not convinced the environment will be favorable. I'd like to see a stronger signal from the dynamical models

[GCANE]

[Kazmit]

Shear will be relaxing, and SSTs increasing. Seems to be favorable for at least some strengthening.

[GCANE]

Looks like a mixed bag on the shear forecast.
COAMPS is not really letting up on it.
The way I read it, could increase quite a bit near the islands.
http://www.nrlmry.navy.mil/coamps-web/w ... =999&scl=2

[GCANE]

This may be in even worse shape than Julia. The circulation is not as defined as is Julia's and it is getting sheared just as badly. There is a chance this opens up within the next 24 hours

COAMPS agrees
http://www.nrlmry.navy.mil/coamps-web/w ... nd850&zm=0

[GCANE]

Convection still can't wrap around the CoC.
Continues getting hammered by the 200mb vort.

[gatorcane]

Continues losing latitude:

http://rammb.cira.colostate.edu/ramsdis ... display=12

[O Town]

This may be in even worse shape than Julia. The circulation is not as defined as is Julia's and it is getting sheared just as badly. There is a chance this opens up within the next 24 hours

They look like the Shear Sisters, fraternal twins.
Albeit I have to agree, Julia looks better naked. Definitely a tighter swirl. Let's see if Karl can hang on

[Alyono]

Karl may be very close to being an open wave now