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The latest microwave imagery suggests TD 5 still has a defined low level circulation center. The first visible/IR imagery of the morning suggests new convection is firing to the N as well as to the S of that CoC. TD 5 is small system and that may help this disturbance to survive the trek across the Caribbean in the days ahead. We will see...

The 06Z Hurricane Models (HWRF & GFDL) are in general agreement of a strengthening system once it nears the NW Caribbean. Both of those models suggest a WNW track across the Caribbean before turn a tad more NW as it passes below Cuba nearing the Yucatan Channel in about 126 hours...

12Z Tracks and Intensity Guidance:

Morning e-mail from Jeff:

Disorganized tropical system heading for the Windward Islands.

Discussion:

Poorly organized TD # 5 moving W at 20mph toward the Windward Islands. Overnight the system has shown little organization with the low level center becoming exposed on the NW side of a ball of deep convection. The combination of dry air to the north of the system and moderate westerly wind shear being driven by an upper level trough to the north is resulting in the poor organization. Conditions do not look to change much for the next 24-48 hours and only modest intensification is expected. It is possible that the system will not be able to overcome the unfavorable conditions and open back up into a tropical wave.

Track:

TD 5 is moving W to WNW south of a large deep layer ridge of high pressure over the central Atlantic Ocean. This ridge extends westward toward the SE US coast and TD 5 will track along the south side of this feature for the next several days. It is a fairly straight forward and medium to high confidence forecast track with the system moving through the Windward Islands on Friday and the Caribbean through the weekend into early next week. Once in the western Caribbean Sea, models begin to diverge with respect to the intensity of the high pressure over the US Gulf coast and the weakness that is expected to develop this weekend over the NE Gulf and track westward toward TX. Some of the models show a NW turn developing suggesting the weakness will be pronounced enough to slow and turn the storm, while others maintain a strong ridge and drive the system W to WNW.

Intensity:

Global models continue to remain split in keeping the system a defined tropical system or opening it back up into a tropical wave. Conditions in the short term are very marginal for development and look to continue on the marginal side for the next 2-3 days. As the system reaches the western Caribbean Sea, conditions look to become more favorable and this is noted by the SHIPS guidance bringing the system to a 75kt hurricane at that point. Interestingly, both the HWRF and especially the GFDL hurricane models do little with this system. Feel it is best to keep the system weaker, near tropical storm status, through the next 3 days, and if it survives then focus on the possibilities of better development potential in the days 4-5 period.

NHC Forecast Track and Error Cone:

Looking over the 12Z suite of track and intensity guidance, we may see a slight shift N and a bit stronger with the next Advisory. The guidance is beginning to suggest the weakness/inverted trough may well be enough to pick up TD 5 as it enter the NW Caribbean and rapidly begins to strengthen. The 06Z GFS Ensembles are in and do not paint an encouraging picture for the NW Gulf as well. We will see.

BULLETIN
TROPICAL DEPRESSION FIVE ADVISORY NUMBER 4
NWS NATIONAL HURRICANE CENTER MIAMI FL AL052012
1100 AM AST THU AUG 02 2012

...DEPRESSION CONTINUES HEADING TOWARD THE WINDWARD ISLANDS...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...13.0N 54.3W
ABOUT 450 MI...725 KM E OF THE WINDWARD ISLANDS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 20 MPH...32 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* BARBADOS...ST. VINCENT AND THE GRENADINES...AND DOMINICA
* ST. LUCIA
* MARTINIQUE AND GUADELOUPE

INTERESTS ELSEWHERE IN THE LESSER ANTILLES SHOULD MONITOR THE
PROGRESS OF THIS SYSTEM.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR
PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 AM AST...1500 UTC...THE CENTER OF TROPICAL DEPRESSION FIVE
WAS LOCATED NEAR LATITUDE 13.0 NORTH...LONGITUDE 54.3 WEST. THE
DEPRESSION IS MOVING TOWARD THE WEST NEAR 20 MPH...32 KM/H...AND
THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 48 HOURS.
ON THE FORECAST TRACK...THE CENTER OF THE DEPRESSION SHOULD BE NEAR
THE WINDWARD ISLANDS ON FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS LIKELY FOR THE NEXT DAY OR
SO...BUT SOME STRENGTHENING IS EXPECTED THEREAFTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB...29.77 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA
ON FRIDAY.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...200 PM AST.
NEXT COMPLETE ADVISORY...500 PM AST.

$$
FORECASTER PASCH

TROPICAL DEPRESSION FIVE DISCUSSION NUMBER 4
NWS NATIONAL HURRICANE CENTER MIAMI FL AL052012
1100 AM AST THU AUG 02 2012

AFTER LOOKING VERY DISORGANIZED OVERNIGHT...SATELLITE IMAGERY THIS
MORNING SHOWS A MARGINALLY BETTER STRUCTURE WITH EVIDENCE OF
INCREASED CONVECTIVE BANDING. NOAA BUOY 41040...TO THE NORTH OF
THE CENTER...REPORTED 31 KT WINDS. THE INTENSITY IS KEPT AT 30 KT
PENDING THE ARRIVAL OF AN AIR FORCE HURRICANE HUNTER AIRCRAFT IN
THE CYCLONE...SCHEDULED FOR 1800 UTC. DYNAMICAL GUIDANCE SHOWS
THAT THE VERTICAL SHEAR SHOULD DECREASE SOMEWHAT IN THE NEXT DAY OR
TWO AND THIS COULD ALLOW FOR SOME STRENGTHENING. HOWEVER THE 1200
UTC SOUNDING FROM TRINIDAD SHOWED A LOW-TO MID-LEVEL EASTERLY JET
TO THE SOUTH OF THE LATITUDE OF THE DEPRESSION...AND THIS COULD BE
AN INHIBITING FACTOR FOR INTENSIFICATION. THE OFFICIAL INTENSITY
FORECAST IS SIMILAR TO THE PREVIOUS ONE.

THE MOTION CONTINUES WESTWARD AT A FAIRLY SWIFT 17 KT. A
MID-TROPOSPHERIC HIGH OVER THE WESTERN ATLANTIC SHOULD MAINTAIN A
WELL-DEFINED EASTERLY STEERING CURRENT OVER THE CARIBBEAN FOR THE
NEXT SEVERAL DAYS. THIS PATTERN IS LIKELY TO KEEP THE CYCLONE ON A
MAINLY WESTWARD TRACK FOR THE NEXT 72 HOURS OR SO. LATER IN THE
FORECAST PERIOD...AS THE SYSTEM NEARS A WEAKNESS IN THE RIDGE...A
GRADUAL TURN TOWARD THE WEST-NORTHWEST IS EXPECTED. THE OFFICIAL
TRACK FORECAST IS NUDGED SLIGHTLY TO THE SOUTH OF THE PREVIOUS
ONE BUT IS OTHERWISE UNCHANGED. THIS IS ALSO VERY CLOSE TO THE
DYNAMICAL MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INIT 02/1500Z 13.0N 54.3W 30 KT 35 MPH
12H 03/0000Z 13.4N 56.9W 30 KT 35 MPH
24H 03/1200Z 13.8N 60.4W 30 KT 35 MPH
36H 04/0000Z 14.1N 63.6W 35 KT 40 MPH
48H 04/1200Z 14.7N 66.8W 40 KT 45 MPH
72H 05/1200Z 15.7N 73.0W 45 KT 50 MPH
96H 06/1200Z 17.0N 78.0W 50 KT 60 MPH
120H 07/1200Z 18.5N 82.0W 60 KT 70 MPH

$$
FORECASTER PASCH

NOUS42 KNHC 021413
REPRPD
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1015 AM EDT THU 02 AUGUST 2012
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 03/1100Z TO 04/1100Z AUGUST 2012
TCPOD NUMBER.....12-076

I. ATLANTIC REQUIREMENTS
TD-05 FLIGHT ONE -- TEAL 72--
A. 03/1800Z-04/0000Z
B. AFXXX 0305A CYCLONE
C. 03/1630Z
D. 14.0N 61.6W
E. 03/1730Z TO 04/2030Z
F. SFC TO 10,000 FT

FLIGHT TWO -TEAL 70-
A. 04/0600, 1200Z
B. AFXXX 0405A CYCLONE
C. 04/0500Z
D. 14.6N 64.9W
E. 04/0530Z TO 04/1200Z
F. SFC TO 10,000 FT

2. OUTLOOK FOR SUCCEEDING DAY: CONTINUE 6-HRLY FIXES.

The 12Z Operational GFS continues to advertise a weak system traversing the Caribbean. Once TD 5 approaches the NW Caribbean, conditions improve and the disturbance slows and begins to organize fairly quickly. What is interesting is the GFS is now suggesting a TS passing very close to the Yucatan Channel with little land interaction which becomes rather concerning for the future development of a potential Hurricane Ernesto.
After entering the Gulf, a future Ernesto continues to develop and head in a general NW direction approaching the NW Gulf Coast...

The key will be how big of a weakness there will be... Stay tuned..

Man, if this thing makes it to the Yucatan Channel as a strong TS (and misses land), watch out!

I'm going to Port A next weekend too - looks like I will need to watch the weather

While the Canadian is not a reliable tropical model, it is interesting to see the 12Z CMC give up the idea of a Florida/East Coast threat and join in the more reliable GFS/Euro solutions of a further W land falling storm...

Yes Srain.

I was just about to post it seems like more and more models are starting to consolidate around the Yucatan turning more NW.

12z HWRF and GFDL are very alike turning NW just past Jamaica
12z UKMET moves a bit south joining the group

The 12Z Euro is further W skirting along the N Coast of Honduras into Belize.

what does the latest GFS model fun show?

ticka1 wrote:what does the latest GFS model fun show?

Near Corpus Christi

Euro doesn't seem to be handling this well at all, much like the last system we had in the Gulf.

12Z HWRF and GFDL suggest a slowly developing system passing just S of Jamaica and heading NW toward the Yucatan Channel. The HWRF is more agressive and develops a Hurricane as well...

18Z: