ATL: HERMINE - Post-Tropical - Discussion

[SouthDadeFish]

Hmmmm.....



I wanna say the low and mid level centers are not aligned yet. LLC looks due north of MLC. But that presumed MLC looks mighty interesting. Even if not aligned at the time of the pass, with how much deep convection is firing they could already be aligned by now. Tough to say without recon. Hopefully they stay decoupled.

[hohnywx]

Anything on RECON scheduled yet? MUST...HAVE...RECON!

 https://twitter.com/FloridaTropics1/status/770993645101146113

[JaxGator]

This buoy has been reporting increasing winds.
http://www.ndbc.noaa.gov/plot_met.php?s ... _label=CDT

[NDG]

I'm sure that the next recon is going to go out to TD 8 instead lol.

[Aric Dunn]

Hmmmm.....

[img]https://s18.postimg.org/516x098jt/TD_9_37_GHz2.jpg[/mg]

I wanna say the low and mid level centers are not aligned yet. LLC looks due north of MLC. But that presumed MLC looks mighty interesting. Even if not aligned at the time of the pass, with how much deep convection is firing they could already be aligned by now. Tough to say without recon. Hopefully they stay decoupled.

I have not been able to get the NRL site to load
yeah does at least there look a little decoupled.

[Aric Dunn]

Anything on RECON scheduled yet? MUST...HAVE...RECON!

 https://twitter.com/FloridaTropics1/status/770993645101146113

still nothing on any of the sites...

[JaxGator]

Ok...no upgrade. Despite the readings this morning....

[Chris_in_Tampa]

Plane is active on NASA tracker. It has not moved yet, still parked at MacDill AFB in Tampa. Takeoff scheduled for 12pm EDT. We'll have to see if they take off early.
http://airbornescience.nasa.gov/tracker ... pid=hybrid

[tolakram]

ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM

TROPICAL DEPRESSION NINE DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
1000 AM CDT WED AUG 31 2016

The system is producing vigorous deep convection, but there is
little organization to the overall cloud pattern. Using the Dvorak
rules, a bursting but disorganized convective pattern would indicate
little change in strength. The intensity is held at 30 kt pending
new observations from a NOAA Hurricane Hunter aircraft in a few
hours. The tropical cyclone should be in a moderate shear
environment, and over very warm water, for the next 36 hours or so.
Therefore, strengthening is forecast and the official forecast
remains close to the intensity model consensus. Given the
reasonably favorable environment, it is appropriate to maintain the
hurricane watch for the northeast Gulf coast at this time. The
intensity forecast after 48 hours is problematic since the system
will be in a decidedly baroclinic environment and under strong
upper-level southwesterly flow. This means that any intensification
that occurs in 2-3 days will likely have a contribution from
baroclinic processes. By 96 hours, the global models depict the
system as embedded in a frontal zone, so extratropical transition is
forecast to occur by that time.

The center is very difficult to locate, but observations from a ship
suggest that there has been little motion since earlier this
morning, so the initial motion estimate is stationary. There has
been little change to the track forecast guidance. A 500-mb trough
over the southeastern United States should cause the cyclone to move
north-northeastward to northeastward across northern Florida and
southeastern Georgia during the next couple of days. Later in the
forecast period there is uncertainty as to how far offshore the
center will move, with some of the global models such as the GFS
and the U.K. Met being close to the northeastern states, and the
ECMWF somewhat farther east. The official track forecast lies
between these two possibilities.

It is important not to focus on the forecast landfall point of this
system. Among other reasons, dangerous storm surge flooding is
likely to extend along the Gulf coast well to the east and south of
the path of the center.

FORECAST POSITIONS AND MAX WINDS

INIT 31/1500Z 24.6N 88.0W 30 KT 35 MPH
12H 01/0000Z 25.9N 87.4W 40 KT 45 MPH
24H 01/1200Z 27.3N 86.5W 45 KT 50 MPH
36H 02/0000Z 29.0N 85.0W 55 KT 65 MPH
48H 02/1200Z 30.9N 82.4W 50 KT 60 MPH...INLAND
72H 03/1200Z 35.0N 75.0W 55 KT 65 MPH...OVER WATER
96H 04/1200Z 38.0N 70.0W 55 KT 65 MPH...POST-TROP/EXTRATROP
120H 05/1200Z 40.0N 69.0W 55 KT 65 MPH...POST-TROP/EXTRATROP

$$
Forecaster Pasch

NNNN

[cdavis6287]

My guess would be landfall between the Gfs and the Nam. I don't really see it going too much further west. Gfs models in very tight consensus and Nam hasn't budged with a little further east trend. I think its gonna be a very close track go TS Colin.

[cycloneye]

TROPICAL DEPRESSION NINE DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092016
1000 AM CDT WED AUG 31 2016

The system is producing vigorous deep convection, but there is
little organization to the overall cloud pattern. Using the Dvorak
rules, a bursting but disorganized convective pattern would indicate
little change in strength. The intensity is held at 30 kt pending
new observations from a NOAA Hurricane Hunter aircraft in a few
hours. The tropical cyclone should be in a moderate shear
environment, and over very warm water, for the next 36 hours or so.
Therefore, strengthening is forecast and the official forecast
remains close to the intensity model consensus. Given the
reasonably favorable environment, it is appropriate to maintain the
hurricane watch for the northeast Gulf coast at this time. The
intensity forecast after 48 hours is problematic since the system
will be in a decidedly baroclinic environment and under strong
upper-level southwesterly flow. This means that any intensification
that occurs in 2-3 days will likely have a contribution from
baroclinic processes. By 96 hours, the global models depict the
system as embedded in a frontal zone, so extratropical transition is
forecast to occur by that time.

The center is very difficult to locate, but observations from a ship
suggest that there has been little motion since earlier this
morning, so the initial motion estimate is stationary. There has
been little change to the track forecast guidance. A 500-mb trough
over the southeastern United States should cause the cyclone to move
north-northeastward to northeastward across northern Florida and
southeastern Georgia during the next couple of days. Later in the
forecast period there is uncertainty as to how far offshore the
center will move, with some of the global models such as the GFS
and the U.K. Met being close to the northeastern states, and the
ECMWF somewhat farther east. The official track forecast lies
between these two possibilities.

It is important not to focus on the forecast landfall point of this
system. Among other reasons, dangerous storm surge flooding is
likely to extend along the Gulf coast well to the east and south of
the path of the center.

FORECAST POSITIONS AND MAX WINDS

INIT 31/1500Z 24.6N 88.0W 30 KT 35 MPH
12H 01/0000Z 25.9N 87.4W 40 KT 45 MPH
24H 01/1200Z 27.3N 86.5W 45 KT 50 MPH
36H 02/0000Z 29.0N 85.0W 55 KT 65 MPH
48H 02/1200Z 30.9N 82.4W 50 KT 60 MPH...INLAND
72H 03/1200Z 35.0N 75.0W 55 KT 65 MPH...OVER WATER
96H 04/1200Z 38.0N 70.0W 55 KT 65 MPH...POST-TROP/EXTRATROP
120H 05/1200Z 40.0N 69.0W 55 KT 65 MPH...POST-TROP/EXTRATROP

$$
Forecaster Pasch

[txwatcher91]

The reason the nam is stronger is its much slower and thus more time to strengthen. dont follow the nam for strength but for the trough placment and speed its a good model for synoptic features. right now its the only model that has this current slow drift/stall thats been going on. it has it lasting for another 24 + hours before it starts moving. something to watch out for if its slower to start moving.

I think the NAM might be a little out there, but I wouldn't be surprised if this system does go in at the Big Bend to be around 960.

It's the 4 km resolution NAM that shows the extreme lower pressure - the 12km and 32km show the 990s range. I don't believe the 4 km mesoscale model show be used for tropical forecasting.

The 12km now takes it into the upper 980s and as noted models typically don't pick up on RI very well. That's why when storms undergo RI it catches people completely off guard. I think it certainly is worth considering as a possibility that could easily happen. This has a solid 36-48 hours over warm water and relatively low shear. That's plenty of time for more than a 75mph hurricane.

[tolakram]

[TheStormExpert]

Geez! What does it take to put a name on this tropical cyclone?

[JKingTampa]

Geez! What does it take to put a name on this tropical cyclone?

An eye.

[tolakram]

Track archive for those interested.

http://www.nhc.noaa.gov/archive/2016/graphics/al09/loop_3W.shtml

[Aric Dunn]

unless it starts moving soon it wont even be close to the 1am tonight position..

[TheStormExpert]

Geez! What does it take to put a name on this tropical cyclone?

An eye.

Seems like it.

300 pages for a tropical cyclone that isn't named is very impressive!

[MississippiWx]

Well, this is something I was worried about earlier with TD9. Organization of MLC/LLC. However, I think evidence from the HH will confirm this is better organized than we originally believed. The NHC is in a tough spot. They don't want to overhype while also needing to get people to take this seriously. If they felt they had sufficient data to upgrade they would do it. This continues to be the ultimate troll of a system.

[ronjon]

Aric, which means it might come in a little stronger, later, and a little further east would be my guess.