000
AXNT20 KNHC 171134
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
705 AM EST THU NOV 17 2011 

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 1115 UTC.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 46W FROM 8N TO 16N.
SCATTERED MODERATE TO ISOLATED STRONG RAINSHOWERS COVER THE 
ATLANTIC OCEAN FROM 7N TO 17N BETWEEN 40W AND 50W. 

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH CURVES THROUGH WESTERN SENEGAL NEAR 14N17W
TO 11N20W AND 8N21W. THE ITCZ CONTINUES FROM 8N21W TO 4N29W
TO 3N36W. ISOLATED MODERATE TO LOCALLY STRONG RAINSHOWERS ARE 
ELSEWHERE TO THE SOUTH OF 10N TO THE EAST OF 50W. UPPER LEVEL 
DIFFLUENT WIND FLOW IS ON TOP OF THE AREA OF THE PRECIPITATION.

...DISCUSSION...

THE GULF OF MEXICO...

MIDDLE LEVEL TO UPPER LEVEL SOUTHWESTERLY WIND FLOW COVERS THE 
GULF OF MEXICO. THE GULF OF MEXICO IS ON THE SOUTHEASTERN SIDE 
OF AN APPROACHING DEEP LAYER TROUGH. THE TROUGH SUPPORTS A COLD 
FRONT THAT STILL IS MOVING THROUGH TEXAS. THE BASE OF THE TROUGH 
IS NEAR 29N92W OFF THE LOUISIANA COAST IN THE NORTHWESTERN GULF 
WATERS. UPPER LEVEL SOUTHEASTERLY WINDS ARE MOVING THROUGH THE 
YUCATAN CHANNEL...BECOMING SOUTHWESTERLY AS THEY HEAD TOWARD 
FLORIDA. THE COLD FRONT NOW PASSES THROUGH THE NORTHWESTERN TIP 
OF THE FLORIDA PANHANDLE...THROUGH EXTREME SOUTHEASTERN 
LOUISIANA...INTO THE NORTHWESTERN GULF WATERS...AND BEYOND THE 
LOWER TEXAS GULF COAST. A PRE-FRONTAL TROUGH IS ALONG 27N87W
BEYOND THE FLORIDA BIG BEND. SCATTERED MODERATE TO ISOLATED 
STRONG RAINSHOWERS ARE WITHIN 15 TO 30 NM ON EITHER SIDE OF
27N85W 30N82W BEYOND 32N80W. 
 
THE CARIBBEAN SEA...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 17N60W 
CYCLONIC CIRCULATION CENTER...ACROSS THE ISLANDS OF THE 
SOUTHEASTERN CARIBBEAN SEA...INTO NORTHEASTERN VENEZUELA.
THE CYCLONIC WIND FLOW COVERS THE AREA TO THE EAST OF 67W.
RAINSHOWERS ARE POSSIBLE FROM 16N TO 19N BETWEEN 56W AND
60W...JUST TO THE EAST OF THE EASTERN CARIBBEAN SEA ISLANDS.
MIDDLE LEVEL TO UPPER LEVEL NORTHEASTERLY TO EASTERLY WIND FLOW 
COVERS MOST OF THE REST OF THE AREA. UPPER LEVEL ANTICYCLONIC 
WIND FLOW COVERS PARTS OF THE WESTERN AND SOUTHWESTERN SECTIONS 
OF THE AREA...TO THE SOUTHWEST OF THE LINE FROM 18N86W TO 
11N78W. THE MONSOON TROUGH PASSES THROUGH 12N74W IN NORTHERN 
COASTAL COLOMBIA...THROUGH 10N80W...AND ALONG 10N BEYOND COSTA 
RICA. ISOLATED MODERATE RAINSHOWERS AND THUNDERSTORMS ARE TO THE 
SOUTH OF 11N BETWEEN 75W AND COSTA RICA/NICARAGUA. RAINSHOWERS 
ARE POSSIBLE ELSEWHERE TO THE EAST OF 84W IN THE SURFACE 
TRADEWIND FLOW THAT IS MOVING THROUGH THE AREA.

THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC CIRCULATION CENTER
IS NEAR 26N74W. LARGE-SCALE ANTICYCLONIC WIND FLOW COVERS THE 
ATLANTIC OCEAN BETWEEN THE 30N49W-TO-NORTHEASTERN VENEZUELA 
TROUGH AND THE SOUTHEASTERN U.S.A. A SURFACE RIDGE EXTENDS FROM 
A 1025 MB HIGH PRESSURE CENTER THAT IS NEAR 34N48W...TO 32N62W 
29N71W...ACROSS THE BAHAMAS AND THE FLORIDA KEYS TO 24N84W IN 
THE SOUTHEASTERN GULF OF MEXICO. AN UPPER LEVEL TROUGH PASSES 
THROUGH 32N14W TO 29N26W. AN UPPER LEVEL SHEAR AXIS CONTINUES 
FROM 29N26W TO 32N33W...CURVING TO 34N38W 32N40W AND 30N49W.
THE SHEAR AXIS TRANSITIONS INTO A MIDDLE LEVEL TO UPPER LEVEL 
TROUGH ALONG 30N49W 25N51W 20N57W...TO A CYCLONIC CIRCULATION 
CENTER THAT IS NEAR 16N60W. THE TROUGH CONTINUES FROM 16N60W
TO THE SOUTHEASTERN CARIBBEAN SEA ISLANDS AND NORTHEASTERN 
VENEZUELA. UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE 
ATLANTIC OCEAN FROM THE ITCZ TO THE SHEAR AXIS AND TO THE EAST 
OF THE 30N49W- TO-VENEZUELA UPPER LEVEL TROUGH. A SURFACE TROUGH 
REMAINS ALONG 28N45W 25N48W 22N50W. WIDELY SCATTERED MODERATE
TO ISOLATED STRONG CONVECTIVE PRECIPITATION IS FROM 8N TO 12N 
BETWEEN 52W AND 60W...AND FROM 24N TO 29N BETWEEN 42W AND 48W. 
RAINSHOWERS ARE POSSIBLE ELSEWHERE WITHIN 400 NM TO THE EAST
OF THE UPPER LEVEL TROUGH.

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

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MT