ATL: HARVEY - Post-Tropical - Discussion

[GCANE]

LLC on VIS is tightening up very quickly.
Hot tower still firing - big helicity with it.

[NDG]

This is where I see the LLC.

[Thetxhurricanemaster]

We have PTC 9
NHC will be initiating advisories at 11 AM AST on Potential Tropical Cyclone Nine, located east of the Windward Islands

[Thetxhurricanemaster]

NHC already made this PTC9 it's developing rather quickly not good for the islands

[RL3AO]

No surprise. I'm curious to see the forecast. If it can stay north of Honduras, that extra 24 to 36 hours could be important for Belize and the Yucatan.

[Thetxhurricanemaster]

No surprise. I'm curious to see the forecast. If it can stay north of Honduras, that extra 24 to 36 hours could be important for Belize and the Yucatan.

It's moving slower and some models predict this could move further north maybe Entering the BOC because it could stall when the trough dives down in 7 days predicted by the models..... that's only assuming there is a trough !

[GCANE]

TXNT24 KNES 171212
TCSNTL

A. TROPICAL DISTURBANCE (91L)

B. 17/1145Z

C. 13.0N

D. 53.3W

E. FIVE/GOES-E

F. T1.5/1.5/D1.0/24HRS

G. IR/EIR/VIS

H. REMARKS...DT=1.5 BASED ON .25 BANDING ON LOG10
SPIRAL. PT=1.5. MET=1.5. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...SCHWARTZ

[ROCK]

we have lift off...

[Thetxhurricanemaster]

..LOW PRESSURE AREA EAST OF THE LESSER ANTILLES EXPECTED TO BECOME A TROPICAL CYCLONE LATER TODAY OR TONIGHT...
11:00 AM AST Thu Aug 17
Location: 13.1°N 54.1°W
Moving: W at 17 mph
Min pressure: 1008 mb
Max sustained: 35 mph

[Thetxhurricanemaster]

They are predicting this to become a category 1 Hurricane as of now !

[GCANE]

09L on RAMMB

[Thetxhurricanemaster]

FORECAST POSITIONS AND MAX WINDS

INIT 17/1500Z 13.1N 54.1W 30 KT 35 MPH...POTENTIAL TROP CYCLONE
12H 18/0000Z 13.1N 56.4W 30 KT 35 MPH...TROPICAL DEPRESSION
24H 18/1200Z 13.2N 59.8W 35 KT 40 MPH
36H 19/0000Z 13.5N 63.2W 40 KT 45 MPH
48H 19/1200Z 13.9N 66.7W 45 KT 50 MPH
72H 20/1200Z 14.5N 74.5W 55 KT 65 MPH
96H 21/1200Z 15.5N 82.0W 65 KT 75 MPH
120H 22/1200Z 17.0N 87.5W 65 KT 75 MPH

[GCANE]

[tolakram]

000
WTNT44 KNHC 171440
TCDAT4

Potential Tropical Cyclone Nine Discussion Number 1
NWS National Hurricane Center Miami FL AL092017
1100 AM AST Thu Aug 17 2017

Satellite imagery, including experimental 1-minute data from
GOES-16, indicates that the circulation of the low pressure area
east of the Lesser Antilles is becoming better defined, and that a
cluster of strong convection has formed just west of the center.
Based on this and the potential for the system to become a tropical
storm before reaching the Lesser Antilles, advisories are being
initiated as a potential tropical cyclone. An Air Force Reserve
Hurricane Hunter aircraft is scheduled to investigate the system
this afternoon, and it is likely the aircraft will find a tropical
cyclone has formed.

The initial motion is 270/15. A deep-layer ridge to the north of
the system should steer it generally just north of due west through
the forecast period, with this motion expected to bring the system
through the Lesser Antilles and into the eastern Caribbean Sea in
24-36 h, into the central Caribbean by 72 h, and to the western
Caribbean by 96-120 h. The forecast track lies near the center of
the tightly clustered guidance envelope and lies near the various
consensus models.

The system is in an area of moderate easterly vertical shear, and
the large-scale models suggest that light/moderate shear should
continue through the forecast period. This seems favorable for
strengthening, and the SHIPS and LGEM models show slow, but steady,
intensification. However, the GFS and ECMWF models forecast the
system to degenerate to an easterly wave over the central Caribbean
Sea, possibly due to dry air entrainment. The intensity forecast
follows the trend of the SHIPS/LGEM models, but it respects the
GFS/ECMWF forecasts by being on the low side of the intensity
guidance envelope.

FORECAST POSITIONS AND MAX WINDS

INIT 17/1500Z 13.1N 54.1W 30 KT 35 MPH...POTENTIAL TROP CYCLONE
12H 18/0000Z 13.1N 56.4W 30 KT 35 MPH...TROPICAL DEPRESSION
24H 18/1200Z 13.2N 59.8W 35 KT 40 MPH
36H 19/0000Z 13.5N 63.2W 40 KT 45 MPH
48H 19/1200Z 13.9N 66.7W 45 KT 50 MPH
72H 20/1200Z 14.5N 74.5W 55 KT 65 MPH
96H 21/1200Z 15.5N 82.0W 65 KT 75 MPH
120H 22/1200Z 17.0N 87.5W 65 KT 75 MPH

$$
Forecaster Beven

[Thetxhurricanemaster]

[i mg]http://www.nhc.noaa.gov/xgtwo/two_atl_2d0.png[/img]

This escalated rather quickly this is forecasted to become a hurricane as of now !

[tolakram]

[wxman57]

They are predicting this to become a category 1 Hurricane as of now !

They went with the statistical SHIPS guidance for intensity. It's often quite poor. Dynamic models aren't developing it much. Most guidance is clustered around 40 kts for peak intensity. A few ensemble members indicate up to hurricane strength.

[Snowman67]

They are predicting this to become a category 1 Hurricane as of now !

They went with the statistical SHIPS guidance for intensity. It's often quite poor. Dynamic models aren't developing it much. Most guidance is clustered around 40 kts for peak intensity. A few ensemble members indicate up to hurricane strength.

What's your take on it ?

[HurricaneBrain]

The models seem to be the only thing stopping the NHC from increasing the intensity in their forecast. Even without model support, they are forecasting a hurricane...

000
WTNT44 KNHC 171440
TCDAT4

Potential Tropical Cyclone Nine Discussion Number 1
NWS National Hurricane Center Miami FL AL092017
1100 AM AST Thu Aug 17 2017

Satellite imagery, including experimental 1-minute data from
GOES-16, indicates that the circulation of the low pressure area
east of the Lesser Antilles is becoming better defined, and that a
cluster of strong convection has formed just west of the center.
Based on this and the potential for the system to become a tropical
storm before reaching the Lesser Antilles, advisories are being
initiated as a potential tropical cyclone. An Air Force Reserve
Hurricane Hunter aircraft is scheduled to investigate the system
this afternoon, and it is likely the aircraft will find a tropical
cyclone has formed.

The initial motion is 270/15. A deep-layer ridge to the north of
the system should steer it generally just north of due west through
the forecast period, with this motion expected to bring the system
through the Lesser Antilles and into the eastern Caribbean Sea in
24-36 h, into the central Caribbean by 72 h, and to the western
Caribbean by 96-120 h. The forecast track lies near the center of
the tightly clustered guidance envelope and lies near the various
consensus models.

The system is in an area of moderate easterly vertical shear, and
the large-scale models suggest that light/moderate shear should
continue through the forecast period. This seems favorable for
strengthening, and the SHIPS and LGEM models show slow, but steady,
intensification. However, the GFS and ECMWF models forecast the
system to degenerate to an easterly wave over the central Caribbean
Sea, possibly due to dry air entrainment. The intensity forecast
follows the trend of the SHIPS/LGEM models, but it respects the
GFS/ECMWF forecasts by being on the low side of the intensity
guidance envelope.

FORECAST POSITIONS AND MAX WINDS

INIT 17/1500Z 13.1N 54.1W 30 KT 35 MPH...POTENTIAL TROP CYCLONE
12H 18/0000Z 13.1N 56.4W 30 KT 35 MPH...TROPICAL DEPRESSION
24H 18/1200Z 13.2N 59.8W 35 KT 40 MPH
36H 19/0000Z 13.5N 63.2W 40 KT 45 MPH
48H 19/1200Z 13.9N 66.7W 45 KT 50 MPH
72H 20/1200Z 14.5N 74.5W 55 KT 65 MPH
96H 21/1200Z 15.5N 82.0W 65 KT 75 MPH
120H 22/1200Z 17.0N 87.5W 65 KT 75 MPH

$$
Forecaster Beven

[Tireman4]

They are predicting this to become a category 1 Hurricane as of now !

They went with the statistical SHIPS guidance for intensity. It's often quite poor. Dynamic models aren't developing it much. Most guidance is clustered around 40 kts for peak intensity. A few ensemble members indicate up to hurricane strength.

So you are thinking NADA for Texas or.......?