ATL: CHANTAL - Post-Tropical

[Gustywind]

Each island of Martinica and Guadeloupe issued at 6AM an yellow alert for a risk of stong showers and tstorms, strong winds, dangereous sea.

http://www.microsofttranslator.com/bv.a ... ilance.php

[Gustywind]

Tropical Chantal Surges Towards the Windward Islands

7/8/2013 5:32:44 AM

http://www.accuweather.com/en/hurricane/atlantic

In the matter of a heartbeat the Atlantic Basin went from being uneventful to more active as Tropical Storm Chantal races westwards towards the Caribbean Sea. Chantal is located about 700 miles to the east-southeast of Barbados and is tracking to the west at near 26 mph. This pace puts Chantal about 24 hours away from a direct impact upon the Windward Islands. Such a rapid rate of speed will preclude any significant strengthening, but Chantal is expected to gradually grow stronger in the coming days.

Tropical storm warnings are in effect for the islands of Barbados, Dominica, Saint Lucia, Martinique and Guadeloupe. A tropical storm watch is in effect for Saint Vincent.

Given the forecast track and speed of movement, wind gusts of 40 mph or greater and heavy rainfall will impact portions of the Windward Islands starting tonight and continuing into Tuesday morning. By Wednesday, the system is expected to be affecting Haiti and eventually far eastern Cuba by the overnight hours. The rapid movement will not only prevent Chantal from becoming a powerful hurricane, but it will also limit the potential for significant flooding. Rainfall amounts of 2-4 inches will be common near the path of the storm, with totals of 6-10 inches possible in the higher terrain.

Chantal is expected to slow down and begin a turn to the northwest later this week. This will bring Chantal near the Bahamas by Friday. At that point the system is expected to be in a weakened state as land interaction and increasing wind shear take its toll on the storm system. While confidence is higher than normal that this will be the case, interests in the region should continue to monitor the progress of this storm as the weather doesn't always work out as planned.

Elsewhere, of additional concern (although not expected to develop into a tropical system) is an area of low pressure high in the atmosphere to the east of the Bahamas. Conditions are not favorable for this feature to develop into a tropical feature, but it will enhance the typical shower and thunderstorm activity across Florida on Tuesday and Wednesday as it moves across the state and into the Gulf of Mexico.

By AccuWeather Meteorologists Randy Adkins and Michael LeSeney

[TreasureIslandFLGal]

I would much rather be on the NHC line at this point, knowing that models usually change this far out.

[falcon]

high-end tropical storm according to ADT

UW - CIMSS ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.4
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 08 JUL 2013 Time : 101500 UTC
Lat : 10:31:50 N Lon : 49:58:26 W


CI# /Pressure/ Vmax
3.5 / 999.9mb/ 55.0kt

[Blown Away]

Many 06z GFS ensembles indicating collapsed steering and possible loop.

[TreasureIslandFLGal]

(sorry, posted in wrong area initially)
I would much rather be on the forecast line at this point, knowing that the models usually change this far out.
So once again, it is all about timing. If this doesn't slow down so much, it could end up further west. -that would not allow the ridge time to break down to the extent needed for the curve to occur before CONUS. It would also gain more longtitude before the approaching trough gets too far east to also assist in the curve, creating the opening for the northward path. Though the faster movement also keeps it from organizing and strengthening much...which usually means a more westward path as well.
Slower in this case will mean an initially stronger storm, more of a curve to stay off the CONUS, and higher likelihood of getting mashed up by the caribbean island mountains too. Taking longer allows the upper level environment more time to become less friendly too, with increased shear expected further down the road. That also would give more time for the trough to show up and for the ridge to break down, letting whatever remains of Chantal to scoot nothward far from the Florida east coast.
-So slow down Baby!

This post is NOT AN OFFICIAL FORECAST and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.

[cycloneye]

A reminder about posting our Storm2k disclaimer when personal statements or long discussions are posted.Thanks for your cooperation.



This post is NOT AN OFFICIAL FORECAST and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.

[Nederlander]

First Vis

[arizona_sooner]

I am on the southwestern side of the island of Trinidad this week. So if Chantal goes against the forecast and maintains its pure westerly course for another day or two, we should get some rain and wind here. Will post a photo or two if it gets interesting...

[cycloneye]

----- Current Analysis -----
Date : 08 JUL 2013 Time : 101500 UTC
Lat : 10:31:50 N Lon : 49:58:26 W


CI# /Pressure/ Vmax
3.5 / 999.9mb/ 55.0kt


Final T# Adj T# Raw T#
3.4 3.4 3.3

Center Temp : -54.8C Cloud Region Temp : -54.2C

Scene Type : IRREGULAR CDO*

Positioning Method : FORECAST INTERPOLATION

Satellite Name : GOES13
Satellite Viewing Angle : 31.5 degrees

[cycloneye]

BULLETIN
TROPICAL STORM CHANTAL INTERMEDIATE ADVISORY NUMBER 2A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL032013
800 AM AST MON JUL 08 2013

...CHANTAL MOVING QUICKLY TOWARD THE LESSER ANTILLES...


SUMMARY OF 800 AM AST...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...10.6N 50.6W
ABOUT 630 MI...1010 KM ESE OF BARBADOS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 26 MPH...43 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


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

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* BARBADOS
* DOMINICA
* SAINT LUCIA
* MARTINIQUE
* GUADELOUPE

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* SAINT VINCENT

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN
24 TO 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE SOMEWHERE IN THE WATCH AREA...IN THIS CASE WITHIN 24 HOURS.

INTERESTS ELSEWHERE IN THE EASTERN CARIBBEAN SHOULD MONITOR THE
PROGRESS OF CHANTAL.

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


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 800 AM AST...1200 UTC...THE CENTER OF TROPICAL STORM CHANTAL WAS
LOCATED NEAR LATITUDE 10.6 NORTH...LONGITUDE 50.6 WEST. CHANTAL IS
MOVING TOWARD THE WEST NEAR 26 MPH...43 KM/H...AND A WEST-
NORTHWESTWARD MOTION AT ABOUT THE SAME FORWARD SPEED IS EXPECTED
OVER THE NEXT COUPLE OF DAYS. ON THE FORECAST TRACK...THE CENTER
OF CHANTAL SHOULD REACH THE LESSER ANTILLES EARLY TUESDAY...AND MOVE
INTO THE EASTERN CARIBBEAN SEA LATER ON TUESDAY.

MAXIMUM SUSTAINED WINDS REMAIN NEAR 40 MPH...65 KM/H...WITH HIGHER
GUSTS. SOME INCREASE IN STRENGTH IS FORECAST DURING THE NEXT 48
HOURS.

TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM
FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB...29.74 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS ARE EXPECTED WITHIN THE WARNING
AREA BY EARLY TUESDAY. TROPICAL STORM CONDITIONS ARE POSSIBLE IN
THE WATCH AREA BY EARLY TUESDAY.

RAINFALL...CHANTAL IS EXPECTED TO PRODUCE RAIN ACCUMULATIONS OF 2 TO
4 INCHES OVER THE LEEWARD AND WINDWARD ISLANDS...WITH MAXIMUM
AMOUNTS OF 6 INCHES POSSIBLE.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 AM AST.

$$
FORECASTER STEWART

[Dave]

000
AXNT20 KNHC 081151
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON JUL 08 2013

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL
ANALYSIS.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...SPECIAL FEATURES...
AS OF 1200 UTC...TROPICAL STORM CHANTAL IS CENTERED NEAR 10.6N
50.6W...OR ABOUT 545 NM ESE OF BARBADOS MOVING W NEAR 23 KT.
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. MAXIMUM SUSTAINED
WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. SEE LATEST NHC
INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS
MIATCPAT3/WTNT33 KNHC AND THE FULL FORECAST/ADVISORY UNDER
AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS.
TROPICAL STORM WATCHES AND WARNINGS HAVE BEEN ISSUED FOR
PORTIONS OF THE LESSER ANTILLES. TOTAL RAIN ACCUMULATIONS OF 2-4
INCHES ARE EXPECTED WITH MAXIMUM OF 6 INCHES POSSIBLE. CURRENTLY
NUMEROUS STRONG CONVECTION IS NEAR THE STORM CENTER FROM 9N-11N
BETWEEN 48W-50W. SCATTERED MODERATE CONVECTION IS ELSEWHERE FROM
8N-12N BETWEEN 47W-52W.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 15N24W TO 7N25W MOVING WEST NEAR 10-15
KT. THE WAVE ALIGNS WITH A LOW-AMPLITUDE 700 MB TROUGH.
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WEST OF THE
WAVE NEAR THE MONSOON TROUGH FROM 5N-9N BETWEEN 26W-30W.

TROPICAL WAVE IS ALONG 22N75W TO 9N80W MOVING WEST AT 15-20 KT.
THE WAVE IS ON THE WEST SIDE OF A SURGE OF DEEP LAYER MOISTURE
PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. SOME DRIER AIR
APPEARS TO BE PRESENT FROM ABOUT 14N-17N. THE NORTHERN PORTION
OF THE WAVE IS ALSO UNDER THE INFLUENCE OF AN UPPER LEVEL LOW
CENTERED NEAR 24N74W. IT IS HARD TO DETERMINE WHICH FEATURE IS
CONTRIBUTING TO CONVECTION IN THE AREA. REGARDLESS...SCATTERED
MODERATE/ISOLATED STRONG CONVECTION IS FROM 22N-28N BETWEEN 68W-
77W. STRONG CONVECTION IS ALSO NEAR THE COAST OF PANAMA FROM 9N-
10N BETWEEN 79W-81W.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA NEAR 11N15W
TO 8N23W 9N33W. THE ITCZ BEGINS NEAR 9N33W AND CONTINUES ALONG
12N42W WHERE IT BREAKS DUE TO TROPICAL STORM CHANTAL. A SMALL
SECTION OF THE ITCZ CONTINUES WEST OF THE STORM ALONG 8N50W TO
5N53W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 7N-
11N BETWEEN 14W-20W.

...DISCUSSION...

GULF OF MEXICO...
WEAK SURFACE RIDGING IS PRESENT OVER THE GULF OF MEXICO
EXTENDING FROM HIGH PRESSURE OVER THE EASTERN CONUS AND WEST
ATLC. HOWEVER...DEEP LAYER MOISTURE REMAINS THROUGHOUT MUCH OF
THE AREA. CURRENTLY...SCATTERED SHOWERS ARE MAINLY ALONG THE
COASTLINE FROM 29N-30N BETWEEN 87W-92W...AND FROM 21N-29N
BETWEEN 95W-100W. THE REMAINDER OF THE BASIN IS MOSTLY CLEAR AT
THIS TIME...ESPECIALLY THE SE CORNER WHERE THERE IS DRIER AIR
ALOFT. ELSEWHERE ALOFT...MOIST AIR STREAMS AROUND AN UPPER LEVEL
RIDGE WITH AXIS FROM THE FLORIDA PANHANDLE NEAR 31N84W TO
27N96W. AT THE SURFACE...EAST TO SOUTHEAST WINDS OF 10-15 KT
SPREAD THROUGHOUT THE BASIN AROUND THE SURFACE RIDGE WITH 20 KT
WINDS OVER THE FAR WESTERN GULF. LITTLE SYNOPTIC CHANGE IS
EXPECTED WITH SURFACE RIDGING DOMINATING THE AREA...AND MOIST
AIR REMAINING OVER THE NW HALF OF THE BASIN.

CARIBBEAN SEA...
MUCH OF THE CARIBBEAN IS EXPERIENCING FAIR CONDITIONS DESPITE
THE PRESENCE OF A TROPICAL WAVE EXTENDING FROM EASTERN CUBA TO
PANAMA. A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE OVER THE NW
CARIBBEAN. STRONGER SHOWERS/THUNDERSTORMS ARE JUST NORTH OF
PANAMA NEAR THE TROPICAL WAVE. THE MONSOON TROUGH MAY ALSO BE
CONTRIBUTING TO THIS ACTIVITY WITH AXIS EXTENDING FROM COSTA
RICA TO NORTHERN COLOMBIA. SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS ARE ALSO MOVING THROUGH THE EASTERN CARIBBEAN EAST
OF 67W ASSOCIATED WITH AN AREA OF INCREASED MOISTURE PRESENT IN
TOTAL PRECIPITABLE WATER IMAGERY. ALOFT...MOSTLY DRY AIR IS
PRESENT AROUND AN UPPER LEVEL RIDGE CENTERED NEAR 13N68W. UPPER
LEVEL TROUGHING IS ONLY OVER THE NW CORNER...BUT IS ACCOMPANIED
BY DRY AIR ALOFT. THE WAVE IS EXPECTED TO CONTINUE MOVING WEST.
TROPICAL STORM CHANTAL IS EAST OF THE LESSER ANTILLES...BUT IS
MOVING QUICKLY AND EXPECTED TO REACH THE ISLANDS BY LATE TONIGHT
OR EARLY TUESDAY MORNING. INTERESTS IN THE EASTERN/CENTRAL
CARIBBEAN SHOULD MONITOR THE PROGRESS OF CHANTAL.

HISPANIOLA...
HISPANIOLA IS RATHER DRY AT THIS TIME. MOISTURE EAST OF THE
TROPICAL WAVE OVER EASTERN CUBA STILL LINGERS NEAR THE
ISLAND...BUT IS MAINLY KEEPING TO THE NORTH AND EAST. TOTAL
PRECIPITABLE WATER IMAGERY INDICATES MORE MOISTURE IS STILL
FARTHER EAST AND COULD IMPACT HISPANIOLA OVER THE NEXT COUPLE OF
DAYS. TROPICAL STORM CHANTAL MAY ALSO IMPACT THE ISLAND BY THE
MIDDLE OF THE WEEK.

ATLANTIC OCEAN...
TROPICAL STORM CHANTAL IS IN THE TROPICAL ATLC. SEE SPECIAL
FEATURES ABOVE. BROAD SURFACE RIDGING DOMINATES THE WEST ATLC
AROUND A 1024 MB HIGH NEAR 34N71W. THE RIDGE IS SUPPORTED BY AN
UPPER LEVEL RIDGE TO THE NORTH CENTERED NEAR 37N64W.
HOWEVER...AN UPPER LEVEL LOW TO THE SOUTH OVER THE BAHAMAS NEAR
24N74W IS ENHANCING ACTIVITY NORTH OF A TROPICAL WAVE NEAR 75W.
SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 22N-28N BETWEEN 68W-
77W. ACROSS THE CENTRAL ATLC...A SURFACE TROUGH...REMNANTS OF A
FRONTAL BOUNDARY ARE ALONG 32N40W 30N46W 27N52W. SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 29N-31N BETWEEN 41W-47W.
AN UPPER TROUGH IS ALONG 35W NORTH OF 23N SUPPORTING THE SURFACE
TROUGH. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE
RIDGING AROUND A 1026 MB HIGH NEAR 31N32W. ALOFT...UPPER RIDGING
DOMINATES THE TROPICAL ATLC AND FAR EASTERN ATLC. VERY DRY AIR
IS THROUGHOUT THE EAST ATLC DUE TO THE PRESENCE OF A BROAD
SAHARAN AIR LAYER...WHICH IS KEEPING CONDITIONS FAIR ACROSS MUCH
OF THE AREA.

FOR ADDITIONAL INFORMATION PLEASE VISIT
http://WWW.HURRICANES.GOV/MARINE

$$
WALTON

[abajan]

----- Current Analysis -----
Date : 08 JUL 2013 Time : 101500 UTC
Lat : 10:31:50 N Lon : 49:58:26 W


CI# /Pressure/ Vmax
3.5 / 999.9mb/ 55.0kt


Final T# Adj T# Raw T#
3.4 3.4 3.3

Center Temp : -54.8C Cloud Region Temp : -54.2C

Scene Type : IRREGULAR CDO*

Positioning Method : FORECAST INTERPOLATION

Satellite Name : GOES13
Satellite Viewing Angle : 31.5 degrees

Yes, when I saw that info posted earlier, I had to check the source for myself, just to be sure. It's quite disconcerting. Hopefully, that wind speed estimate is wrong.

[tolakram]

Live visible loop, no java required.

zoom1: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... umframes=5

zoom2: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... umframes=5

11:15Z

[NDG]

Latest microwave pass shows me that most of the convection is south of the LLC, IMO.

[Dave]

Cycloneye, I'm going to clear out my personal work this morning and will be ready to go for takeoff this afternoon.

[cycloneye]

Cycloneye, I'm going to clear out my personal work this morning and will be ready to go for takeoff this afternoon.

Ok,ready to go this afternoon at 2:15 PM EDT when plane departs from St Croix.

[Dave]

Cycloneye, I'm going to clear out my personal work this morning and will be ready to go for takeoff this afternoon.

Ok,ready to go this afternoon at 2:15 PM EDT when plane departs from St Croix.

Got it...will check in around 1 - 1:30 PM EDT

[wxman57]

It's hard to tell, but the circulation center may be WNW of the NHC position - out ahead of the convection. Note the outflow boundaries moving away from Chantal in the northern semicircle. Not a sign of strengthening.

[GCANE]

Live visible loop, no java required.

zoom1: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... umframes=5

zoom2: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... umframes=5

11:15Z
http://imageshack.us/a/img692/604/u48a.jpg

Pretty obvious cirrus CDO building from the overshooting tops firing off at DMAX.