ATL: DORIAN - Post-Tropical - Discussion

[artist]

latest Dvorak image -

[Gustywind]

Those who lived in the Leewards islands should continue to monitor Dorian's progress. Again let's see what really could pan's out from this TS.

http://www.accuweather.com/en/weather-n ... e/15685176


Tropical Storm Dorian to Approach Leewards This Weekend

By Alex Sosnowski, Expert Senior Meteorologist
July 24, 2013; 8:06 AMMore Sharing ServicesShare | Share on facebookShare on twitterShare on linkedin


A tropical system that moved off the coast of Africa last weekend has become the fourth tropical storm of the 2013 Atlantic season Wednesday.

A slightly north of west path is forecast with Dorian through this weekend into early next week, most likely taking the feature close to or just north of the Lesser Antilles.

Conditions in the Leeward Islands this weekend will depend upon the exact path and strength of the tropical storm. There is a possibility of gusty, drenching squalls developing in the area late Saturday and continuing into Sunday, if the system were to track close by.

According to Hurricane Expert Dan Kottlowski, "The vast area of dry air surrounding the system to start the week has diminished and would tend to favor strengthening during the middle of the week."

The system may have already been a tropical storm early Wednesday morning. Enhanced satellite images during the morning hours indicated a concentrated area of thunderstorms with some rotation.

At 10:30 a.m. EDT Wednesday, winds were estimated to be sustained at 50 mph near the center of Dorian.

Official investigation by the National Hurricane Center will continue. Sustained winds must reach 74 mph for the system to be classified as a hurricane.

"Later this week, Dorian will move into a zone of cooler waters, which may cause the system to plateau or even weaken," Kottlowski stated.

The path of Dorian next week will depend on the strength of the tropical system itself and other weather systems surrounding it.

"It is too early to say with confidence for next week where Dorian will track and what the strength will be," Kottlowski added.

It could be scooped up by the back side of high pressure near Bermuda over the Atlantic Ocean. In this scenario, the feature could then travel along the East Coast of the United States.

Another scenario allows Dorian to miss the "right turn lane" and continue west-northwestward brushing northern shores of Puerto Rico, Hispaniola and Cuba.

[northjaxpro]

Well, if Dorian can build a strong inner core, then I think the cyclone will have a pretty decent chance of surviving the shear ahead of it. However, it does seem that based on intensity forecasts by the models, the shear may not be as strong as intially thought in the next couple of days.

But, always remember that although we have seen improvements of analyzing intensity of tropical cyclones the past few years, this is still always and will remain the toughest aspect in tropical cyclone forecasting.

[lester]

The Public Advisory and Discussion still isn't out yet despite it showing it is out on the website...

it's out, the website must be having some problems

[CrazyC83]

ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM

TROPICAL STORM DORIAN DISCUSSION NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042013
1100 AM EDT WED JUL 24 2013

VISIBLE SATELLITE IMAGERY AND RECENT ASCAT SCATTEROMETER WINDS
INDICATE THAT THE TROPICAL DEPRESSION HAS BECOME BETTER ORGANIZED
AND HAS STRENGTHENED INTO TROPICAL STORM DORIAN. THE INITIAL
INTENSITY OF 45 KT IS BASED ON A 38-KT ASCAT SURFACE WIND AT
1111Z... AND VARIOUS OBJECTIVE SATELLITE INTENSITY ESTIMATES OF
ABOUT 45 KT.

THE INITIAL MOTION ESTIMATE IS 285/18 KT. DORIAN IS EXPECTED TO BE
STEERED WEST-NORTHWESTWARD TO WESTWARD BY A STRONG DEEP-LAYER
SUBTROPICAL RIDGE OVER THE CENTRAL AND EASTERN ATLANTIC. THE NHC
MODEL GUIDANCE REMAINS TIGHTLY PACKED IN EXCELLENT AGREEMENT ON
THIS TRACK SCENARIO...WITH THE ONLY DIFFERENCES BEING SLIGHT
VARIATIONS IN THE FORWARD SPEED. THE NHC OFFICIAL FORECAST TRACK IS
SIMILAR TO THE PREVIOUS ADVISORY AND IS CLOSE TO THE MULTI-MODEL
CONSENSUS TVCN.

FOR THE NEXT 24 HOURS OR SO...THE VERTICAL SHEAR IS FORECAST TO BE
VERY LOW WHILE DORIAN REMAINS OVER MARGINALLY WARM SSTS. HOWEVER...
DURING THE 24-48 HOUR TIME PERIOD...DORIAN WILL BE MOVING OVER 25C
SSTS...WHICH COULD INDUCE SOME SLIGHT WEAKENING. THE CYCLONE IS
EXPECTED TO MAINTAIN THE CURRENT FAVORABLE EQUATORIAL INFLOW OF
WARM UNSTABLE AIR THAT IS OFFSETTING THE COOLER MORE STABLE AIR
BEING INGESTED FROM THE NORTH...AND THAT COULD OFFSET THE EFFECTS
OF DORIAN PASSING OVER COOLER WATERS. FOR THAT REASON...THE
INTENSITY FORECAST ONLY SHOWS SLIGHT WEAKENING AT 36- AND 48-HOURS.
AFTER THAT...THE CYCLONE IS LIKELY TO ENCOUNTER BOTH WARMER WATER
AND INCREASING WESTERLY SHEAR...SO THE INTENSITY FORECAST IS HELD
STEADY. THE OFFICIAL INTENSITY FORECAST IS SLIGHTLY HIGHER THAN THE
PREVIOUS ADVISORY THROUGH THE NEXT 24 HOURS DUE TO THE HIGHER
INITIAL INTENSITY...BUT THEN FOLLOWS THE TREND OF CONSENSUS MODELS.

FORECAST POSITIONS AND MAX WINDS

INIT 24/1500Z 14.3N 29.9W 45 KT 50 MPH
12H 25/0000Z 15.0N 32.6W 50 KT 60 MPH
24H 25/1200Z 15.8N 36.1W 50 KT 60 MPH
36H 26/0000Z 16.4N 39.8W 45 KT 50 MPH
48H 26/1200Z 17.1N 43.4W 40 KT 45 MPH
72H 27/1200Z 18.3N 51.2W 40 KT 45 MPH
96H 28/1200Z 19.3N 58.2W 40 KT 45 MPH
120H 29/1200Z 20.1N 64.0W 40 KT 45 MPH

$$
FORECASTER STEWART

NNNN

From the text-based format site...

[lester]

991
WTNT34 KNHC 241430
TCPAT4

BULLETIN
TROPICAL STORM DORIAN ADVISORY NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042013
1100 AM EDT WED JUL 24 2013

..FOURTH NAMED STORM OF THE 2013 SEASON FORMS



SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...14.3N 29.9W
ABOUT 410 MI...660 KM WSW OF THE CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 21 MPH...33 KM/H
MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES


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


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
SATELLITE IMAGERY AND DATA INDICATE THAT THE TROPICAL DEPRESSION IN
THE EASTERN TROPICAL ATLANTIC HAS STRENGTHENED THIS MORNING.

AT 1100 AM EDT...1500 UTC...THE CENTER OF TROPICAL STORM DORIAN WAS
LOCATED NEAR LATITUDE 14.3 NORTH...LONGITUDE 29.9 WEST. DORIAN IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 21 MPH...33 KM/H...AND THIS
GENERAL MOTION IS EXPECTED TO CONTINUE DURING THE NEXT COUPLE OF
DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 50 MPH...85 KM/H...WITH HIGHER
GUSTS. SOME SLIGHT STRENGTHENING IS POSSIBLE TODAY...FOLLOWED BY
GRADUAL WEAKENING ON THURSDAY AS DORIAN MOVES OVER COOLER WATER.

TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB...29.59 INCHES.


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


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 PM EDT.



025
WTNT44 KNHC 241431
TCDAT4

TROPICAL STORM DORIAN DISCUSSION NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042013
1100 AM EDT WED JUL 24 2013

VISIBLE SATELLITE IMAGERY AND RECENT ASCAT SCATTEROMETER WINDS
INDICATE THAT THE TROPICAL DEPRESSION HAS BECOME BETTER ORGANIZED
AND HAS STRENGTHENED INTO TROPICAL STORM DORIAN. THE INITIAL
INTENSITY OF 45 KT IS BASED ON A 38-KT ASCAT SURFACE WIND AT
1111Z... AND VARIOUS OBJECTIVE SATELLITE INTENSITY ESTIMATES OF
ABOUT 45 KT.

THE INITIAL MOTION ESTIMATE IS 285/18 KT. DORIAN IS EXPECTED TO BE
STEERED WEST-NORTHWESTWARD TO WESTWARD BY A STRONG DEEP-LAYER
SUBTROPICAL RIDGE OVER THE CENTRAL AND EASTERN ATLANTIC. THE NHC
MODEL GUIDANCE REMAINS TIGHTLY PACKED IN EXCELLENT AGREEMENT ON
THIS TRACK SCENARIO...WITH THE ONLY DIFFERENCES BEING SLIGHT
VARIATIONS IN THE FORWARD SPEED. THE NHC OFFICIAL FORECAST TRACK IS
SIMILAR TO THE PREVIOUS ADVISORY AND IS CLOSE TO THE MULTI-MODEL
CONSENSUS TVCN.

FOR THE NEXT 24 HOURS OR SO...THE VERTICAL SHEAR IS FORECAST TO BE
VERY LOW WHILE DORIAN REMAINS OVER MARGINALLY WARM SSTS. HOWEVER...
DURING THE 24-48 HOUR TIME PERIOD...DORIAN WILL BE MOVING OVER 25C
SSTS...WHICH COULD INDUCE SOME SLIGHT WEAKENING. THE CYCLONE IS
EXPECTED TO MAINTAIN THE CURRENT FAVORABLE EQUATORIAL INFLOW OF
WARM UNSTABLE AIR THAT IS OFFSETTING THE COOLER MORE STABLE AIR
BEING INGESTED FROM THE NORTH...AND THAT COULD OFFSET THE EFFECTS
OF DORIAN PASSING OVER COOLER WATERS. FOR THAT REASON...THE
INTENSITY FORECAST ONLY SHOWS SLIGHT WEAKENING AT 36- AND 48-HOURS.
AFTER THAT...THE CYCLONE IS LIKELY TO ENCOUNTER BOTH WARMER WATER
AND INCREASING WESTERLY SHEAR...SO THE INTENSITY FORECAST IS HELD
STEADY. THE OFFICIAL INTENSITY FORECAST IS SLIGHTLY HIGHER THAN THE
PREVIOUS ADVISORY THROUGH THE NEXT 24 HOURS DUE TO THE HIGHER
INITIAL INTENSITY...BUT THEN FOLLOWS THE TREND OF CONSENSUS MODELS.

FORECAST POSITIONS AND MAX WINDS

INIT 24/1500Z 14.3N 29.9W 45 KT 50 MPH
12H 25/0000Z 15.0N 32.6W 50 KT 60 MPH
24H 25/1200Z 15.8N 36.1W 50 KT 60 MPH
36H 26/0000Z 16.4N 39.8W 45 KT 50 MPH
48H 26/1200Z 17.1N 43.4W 40 KT 45 MPH
72H 27/1200Z 18.3N 51.2W 40 KT 45 MPH
96H 28/1200Z 19.3N 58.2W 40 KT 45 MPH
120H 29/1200Z 20.1N 64.0W 40 KT 45 MPH


FORECASTER STEWART

[tolakram]

14:15Z

[ROCK]

06Z NAVGEM.....uh FL you need to pay attention to Dorian.

https://www.fnmoc.navy.mil/wxmap_cgi/cg ... t=Tropical

[Gustywind]

Tropical Storm Dorian in the Eastern Atlantic

Published: Jul 24, 2013, 10:33 AM EDT weather.com

http://www.weather.com/news/weather-hur ... c-20130723

Tropical Storm Dorian strengthened quickly Wednesday, after first designated as "Tropical Depression Four" just before 5 a.m. EDT over the far eastern Atlantic Ocean, southwest of the Cape Verde Islands.

Dorian will track toward the west-northwest over the next several days on the south side of an intensifying Bermuda-Azores high, and will remain over open waters through the weekend.

It may approach the Leeward Islands late Sunday night or early Monday morning, though it's not clear whether the system will track to the north of the islands at this early timeframe.

Additionally, this all assumes this system will survive the voyage. Some dry air lurks ahead of the system, and wind shear is expected to increase over the system late this week. These ingredients are both hostile to tropical cyclones.

Interests in the Leeward Islands, including Puerto Rico and the U.S. Virgin Islands, should monitor the progress of this system.

[tolakram]

Latest AVN image is interesting.

This is from 14:45Z

[DESTRUCTION5]

Latest AVN image is interesting.

This is from 14:45Z

http://imageshack.us/a/img801/9549/yunl.jpg

Wow...July Who?

[Blown Away]

Very cool pic...

[WeatherGuesser]

Good, bad or indifferent, major media is already picking up on it.

[Gustywind]

The title should be edited as TD 4 has increased to TS Dorian.

[CalmBeforeStorm]

http://www.ssd.noaa.gov/PS/TROP/floater ... short.html
~~~~~~~~~~
Looks very small and fragile to me. If conditions do become hostile which would be normal for July, I think it has very little chance to survive.

[tolakram]

14:45Z visible



This was the global pass, here is a link to a large scape image:

http://imageshack.us/a/img42/2456/hhg1.jpg

[northtxboy]

Holy crap,!!!!! He is lookin good this morning. I am late to the party as always. Is it possible that he gets stronger over cooler waters? Has that ever happened before?

[SFLcane]

06Z NAVGEM.....uh FL you need to pay attention to Dorian.

https://www.fnmoc.navy.mil/wxmap_cgi/cg ... t=Tropical

Well it's true I think this TS will have its opportunity to strengthen in the long term and Florida's sake lets hope shear and dry air prevent things from getting out of hand.

[AtlanticWind]

http://www.ssd.noaa.gov/PS/TROP/floaters/04L/flash-vis-short.html
~~~~~~~~~~
Looks very small and fragile to me. If conditions do become hostile which would be normal for July, I think it has very little chance to survive.

You Have something against small storms ?

[CalmBeforeStorm]

http://www.ssd.noaa.gov/PS/TROP/floaters/04L/flash-vis-short.html
~~~~~~~~~~
Looks very small and fragile to me. If conditions do become hostile which would be normal for July, I think it has very little chance to survive.

You Have something against small storms ?

Some of my favorite storms were small