ATL: HELENE - Post-Tropical

[MGC]

It all depends on what that ULL over Cuba does.....If it hangs around the shear will rip DT7 apart...if it clears out conditions might not be that hostile....time will tell.....MGC

[Camille(CaneOnAPill)]

Ernie's biggest issue, IMO, wasn't dry air, it was the llc continuously outrunning the mlc. He never could get a stacked shot to 200mb in the central/eastern Caribbean. Otherwise, I think he could have digested the small amount of midlevel dry air that he encountered. And if you believe the BAM suite, being too fast for your own good looks to be the fate for TD7 as well.. Things change daily though. Won't be paying too much attention to this for a while.

This may sound like a silly question, but what causes the speed of tropical waves coming off of Africa to vary as they develop in the open waters of the Atlantic? Also, what is the maximum speed a system can be moving and still attain a developing core without the lower and mid levels continuing to separate?

[cycloneye]

00z Best Track

Remains as Tropical Depression Seven.

AL, 07, 2012081000, , BEST, 0, 137N, 446W, 30, 1009, TD

ftp://ftp.nhc.noaa.gov/atcf/tcweb/inves ... 012.invest

[cycloneye]

00z Models

Code: Select all

WHXX01 KWBC 100047
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS NATIONAL HURRICANE CENTER MIAMI FL
0047 UTC FRI AUG 10 2012
 
DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.
 
ATLANTIC OBJECTIVE AIDS FOR
 
TROPICAL CYCLONE SEVEN (AL072012) 20120810 0000 UTC
 
        ...00 HRS...   ...12 HRS...   ...24 HRS. ..   ...36 HRS...
        120810  0000   120810  1200   120811  0000   120811  1200
 
         LAT    LON     LAT    LON     LAT    LON     LAT    LON
BAMS    13.7N  44.6W   14.0N  47.9W   14.4N  51.3W   15.0N  54.7W
BAMD    13.7N  44.6W   13.9N  47.1W   14.3N  49.3W   15.0N  51.4W
BAMM    13.7N  44.6W   14.0N  47.4W   14.5N  50.1W   15.1N  52.8W
LBAR    13.7N  44.6W   13.7N  47.8W   14.0N  51.1W   14.4N  54.4W
SHIP        30KTS          35KTS          42KTS          48KTS
DSHP        30KTS          35KTS          42KTS          48KTS
 
        ...48 HRS...   ...72 HRS...   ...96 HRS. ..   ..120 HRS...
        120812  0000   120813  0000   120814  0000   120815  0000
 
         LAT    LON     LAT    LON     LAT    LON     LAT    LON
BAMS    15.5N  58.2W   16.4N  65.1W   17.7N  71.6W   19.3N  77.1W
BAMD    16.0N  53.1W   18.7N  56.0W   21.7N  58.5W   23.5N  59.9W
BAMM    15.8N  55.2W   17.4N  59.3W   19.5N  62.4W   21.3N  65.0W
LBAR    15.0N  57.4W   16.8N  62.1W   19.5N  64.9W   21.4N  65.8W
SHIP        51KTS          54KTS          56KTS          60KTS
DSHP        51KTS          54KTS          56KTS          60KTS
 
         ...INITIAL CONDITIONS...
LATCUR =  13.7N LONCUR =  44.6W DIRCUR = 270DEG SPDCUR =  17KT
LATM12 =  13.7N LONM12 =  41.7W DIRM12 = 266DEG SPDM12 =  14KT
LATM24 =  14.1N LONM24 =  38.5W
WNDCUR =   30KT RMAXWD =   40NM WNDM12 =   25KT
CENPRS = 1009MB OUTPRS = 1013MB OUTRAD =  100NM SDEPTH =   M
RD34NE =    0NM RD34SE =    0NM RD34SW =    0NM RD34NW =   0NM


[WilmingtonSandbar]

People on this thread are calling TD7 Gordon or G. 93L might beat this storm to that name.

[gatorcane]

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.

I took another look at this system tonight and I still can't see why the NHC pulled the trigger on it today calling it a depression. It clearly is battling with the SAL and convection is weakening around the center and becoming more disorganized. The convection has yet to be sustained convection.

With the ECMWF and GFS not calling for any significant development and both calling for a fast westward track through the Caribbean, the forecast is fairly straightforward on this one to me. It's possible once it gets way west into the Western Caribbean we could see some more organization, but that is many days away and we have plenty of time to watch.

[HurrMark]

This thing looks horrible tonight. I guess we have to wait till the vis comes in, but it wouldn't surprise me to see this thing quickly degenerate into an open wave. The trades are killing it...there is virtually no convection near the center...virtually all of it is well displaced to the southwest.

[ozonepete]

You would think everyone had learned a lesson about calling a storm dead after they did it erroneously with Ernesto. And that was just a few days ago, lol.

[Typhoon_Willie]

Looks like this system may track a bit closer to the Greater Antilles than Ernesto did. This is judging from the above post from Cycloneye.

[meriland23]

Looks more in favor of a more SW direction, even CLP5 is much further south

[Portastorm]

Looks more in favor of a more SW direction, even CLP5 is much further south

The CLP5 is a climatology/persistence model. All it will show is a straight-line projection of the storm's recent movement.

[Nikki]

I know things can and will change many, many times but right now these models seem to really favor the GOM.


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.

[Weatherfreak000]

Over time, sometimes members can forget about the diurnal maxima/minimum. These effects are tricky to predict, and as some members said it can be a bad idea to write a storm off prematurely.


Conditions appear dry but not enough to kill future Gordon. We can only wait and see.

[Annie Oakley]

Ahhh..what are the allowances in the Models thread lol? Model-posting and discussion I take it?
Just thinking here.
In Recon there is a dedicated thread to stats and a separate one for discussion of same. Wondering if same application should be for Models talk and postings....

[cycloneye]

WTNT22 KNHC 100236
TCMAT2

TROPICAL DEPRESSION SEVEN FORECAST/ADVISORY NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072012
0300 UTC FRI AUG 10 2012

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

INTERESTS IN THE WINDWARD ISLANDS SHOULD MONITOR THE PROGRESS OF
THIS SYSTEM. TROPICAL STORM WATCHES COULD BE REQUIRED ON FRIDAY
MORNING.

TROPICAL DEPRESSION CENTER LOCATED NEAR 13.7N 45.5W AT 10/0300Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 17 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1009 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 13.7N 45.5W AT 10/0300Z
AT 10/0000Z CENTER WAS LOCATED NEAR 13.7N 44.6W

FORECAST VALID 10/1200Z 13.6N 48.1W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 30NE 0SE 0SW 30NW.

FORECAST VALID 11/0000Z 13.6N 51.7W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 30NE 0SE 0SW 30NW.

FORECAST VALID 11/1200Z 13.7N 55.3W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 40NE 0SE 0SW 40NW.

FORECAST VALID 12/0000Z 14.1N 58.8W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 50NE 0SE 0SW 50NW.

FORECAST VALID 13/0000Z 14.9N 65.5W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 60NE 20SE 20SW 60NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 175 NM
ON DAY 4 AND 225 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 14/0000Z 16.0N 71.5W
MAX WIND 45 KT...GUSTS 55 KT.

OUTLOOK VALID 15/0000Z 17.0N 78.0W
MAX WIND 45 KT...GUSTS 55 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.7N 45.5W

NEXT ADVISORY AT 10/0900Z

$$
FORECASTER BLAKE



WTNT32 KNHC 100236
TCPAT2

BULLETIN
TROPICAL DEPRESSION SEVEN ADVISORY NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072012
1100 PM AST THU AUG 09 2012

...TROPICAL DEPRESSION CONTINUES MOVING RAPIDLY WESTWARD...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...13.7N 45.5W
ABOUT 1045 MI...1680 KM E OF THE WINDWARD ISLANDS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 20 MPH...32 KM/H
MINIMUM CENTRAL PRESSURE...1009 MB...29.80 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

INTERESTS IN THE WINDWARD ISLANDS SHOULD MONITOR THE PROGRESS OF
THIS SYSTEM. TROPICAL STORM WATCHES COULD BE REQUIRED ON FRIDAY
MORNING.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM AST...0300 UTC...THE CENTER OF TROPICAL DEPRESSION SEVEN
WAS LOCATED NEAR LATITUDE 13.7 NORTH...LONGITUDE 45.5 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.

MAXIMUM SUSTAINED WINDS REMAIN NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...
AND THE DEPRESSION COULD BECOME A TROPICAL STORM ON FRIDAY.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1009 MB...29.80 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 AM AST.

$$
FORECASTER BLAKE


WTNT42 KNHC 100240
TCDAT2

TROPICAL DEPRESSION SEVEN DISCUSSION NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL AL072012
1100 PM AST THU AUG 09 2012

A SMALL AREA OF CONVECTION HAS PERSISTED NEAR THE CENTER OF THE
DEPRESSION DURING THE PAST SEVERAL HOURS...ALTHOUGH THERE ARE NO
BANDING FEATURES APPARENT. WITH NO SIGNIFICANT CHANGES IN THE
SATELLITE INTENSITY ESTIMATES...THE INITIAL INTENSITY WILL REMAIN
30 KT. THE CENTER OF THE CYCLONE SHOULD MOVE CLOSE TO NOAA BUOY
41041 OVERNIGHT...WHICH SHOULD PROVIDE A BETTER LOOK AT THE
INTENSITY. ALTHOUGH THE WIND SHEAR IS LIGHT FOR NOW...THE
ENVIRONMENT AROUND THE DEPRESSION ALWAYS SEEMS TO HAVE SOME
NEGATIVE FACTORS THROUGHOUT THE FORECAST PERIOD. THERE IS PLENTY
OF DRY AIR AND MARGINAL THERMODYNAMICS NEAR THE CIRCULATION
INITIALLY...WHICH IS PROBABLY RESPONSIBLE FOR THE LACKLUSTER
CONVECTION. AS THE SYSTEM MOVES WESTWARD OVER WARMER WATERS...THE
INSTABILITY SHOULD RISE...BUT THE SHEAR SHOULD ALSO INCREASE
WITHIN 24 TO 36 HOURS DUE TO A LARGE MID-OCEANIC TROUGH. THIS
SHEAR IS LIKELY TO FURTHER INCREASE AS THE CYCLONE APPROACHES THE
TROUGH. THE OFFICIAL FORECAST CONTINUES THE TREND OF THE PREVIOUS
FORECAST...SHOWING ONLY GRADUAL INTENSIFICATION THROUGH 48 HOURS.
THE DAY 4 AND 5 PREDICTIONS HAVE BEEN REDUCED GIVEN THE LIKELY
PERSISTENCE OF THE SHEAR AND THE CLIMATOLOGICAL NON-DEVELOPMENT
TREND IN THE CENTRAL CARIBBEAN SEA.

THE INITIAL MOTION CONTINUES AT 270/17. THIS GENERAL TRACK AND
SPEED IS LIKELY FOR THE NEXT COUPLE OF DAYS AS A MID-LEVEL RIDGE
PERSISTS NORTH OF THE DEPRESSION. AFTER THAT TIME...THERE ARE
INDICATIONS FROM THE GLOBAL MODELS THAT THE RIDGE COULD WEAKEN
SOMEWHAT...AND THERE HAS BEEN A SUBTLE SHIFT TO A MORE WEST-
NORTHWEST COURSE IN MOST OF THE GUIDANCE BEYOND 36 HOURS. THE
NEW FORECAST...HOWEVER...STAYS ON THE SOUTHWEST SIDE OF THE
GUIDANCE ENVELOPE AND IS JUST A BIT NORTH OF THE PREVIOUS ONE...
SINCE THE MODELS HAVE BEEN KNOWN TO HAVE A SLOW AND POLEWARD BIAS
WITH LOW-LATITUDE SYSTEMS IN THIS AREA.


FORECAST POSITIONS AND MAX WINDS

INIT 10/0300Z 13.7N 45.5W 30 KT 35 MPH
12H 10/1200Z 13.6N 48.1W 35 KT 40 MPH
24H 11/0000Z 13.6N 51.7W 35 KT 40 MPH
36H 11/1200Z 13.7N 55.3W 40 KT 45 MPH
48H 12/0000Z 14.1N 58.8W 45 KT 50 MPH
72H 13/0000Z 14.9N 65.5W 45 KT 50 MPH
96H 14/0000Z 16.0N 71.5W 45 KT 50 MPH
120H 15/0000Z 17.0N 78.0W 45 KT 50 MPH

$$
FORECASTER BLAKE

[vbhoutex]

EVERYONE, please let's be careful about calling a developing system by a name even if you say future, especially when there are 2 or more systems in the same basin in the developmental stage. One never knows for sure what could happen and it may not become the named system you think it will. This will also help avoid any confusion until the system is actually named by NHC.

[WilmingtonSandbar]

Over time, sometimes members can forget about the diurnal maxima/minimum. These effects are tricky to predict, and as some members said it can be a bad idea to write a storm off prematurely.


Conditions appear dry but not enough to kill future Gordon. We can only wait and see.

I think "future Gordon" just came off of Africa, personally.

[cycloneye]

[Weatherfreak000]

http://tropic.ssec.wisc.edu/real-time/w ... oom=&time=

Apologize to the admin for the confusion.


Taking a look at shear tendency profile shear is not an issue for either invest. It appears shear may not be sure a problem for TD7 for the short term. Man it's just coming in way too fast...given how negative features are present throughout the forecast period maybe it can outrun them.

[ROCK]

I know things can and will change many, many times but right now these models seem to really favor the GOM.


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.

yes it does... if it survives....