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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 081750
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
105 PM EST SUN DEC 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...SPECIAL FEATURES...                                       
ATLANTIC BASIN...A GALE WARNING IS IN EFFECT FOR THE CENTRAL 
ATLC N OF 28N BETWEEN 40W-47W UNTIL 09/0600 UTC. THESE NW TO N 
WINDS ARE ASSOCIATED WITH THE 1002 MB GALE CENTER NEAR 29N41W. 
PLEASE SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS 
MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.  

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE TROPICAL 
ATLC NEAR 6N11W TO 5N16W WHERE THE ITCZ BEGINS AND CONTINUES 
ALONG 4N21W 7N32W TO E OF A SURFACE TROUGH NEAR 8N41W. A SURFACE 
TROUGH IS ANALYZED ALONG 43W FROM 6N-2N. CLUSTERS OF SCATTERED 
MODERATE CONVECTION ARE FROM 6N-10N BETWEEN 33W-40W. 

...DISCUSSION...

GULF OF MEXICO...                                                
A LARGE UPPER RIDGE OVER THE NW CARIBBEAN EXTENDS OVER THE SW 
ATLC GIVING THE GULF SW FLOW ALOFT. A BROAD UPPER TROUGH OVER 
CANADA AND THE FAR N ATLC IS SUPPORTING A COLD FRONT IN THE NW 
ATLC AND ENTERS THE GULF AS A STATIONARY FRONT AT 08/1500 UTC 
ACROSS TALLAHASSEE FLORIDA TO 29N87W WHERE IT BECOMES A WARM 
FRONT ALONG 27N94W TO 24N95W THEN BECOMES STATIONARY AGAIN TO 
THE CENTRAL BAY OF CAMPECHE NEAR 19N94W. SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS ARE N OF 28N BETWEEN 91W-95W TO INLAND 
OVER LOUISIANA AND FAR E TEXAS. THE REMAINDER OF THE AREA W OF 
THE FRONT IS UNDER DENSE LOW/MID CLOUDS WITH POSSIBLE ISOLATED 
SHOWERS TO OVER THE SE CONUS AND NE MEXICO. THIS IS LEAVING THE 
REMAINDER OF THE GULF UNDER MOSTLY CLEAR SKIES THIS AFTERNOON. 
THE WARM FRONT WILL CONTINUE TO MOVE NW AND STALL OVER THE NW 
GULF EARLY MON. A COLD FRONT WILL MOVE INTO THE NW GULF ON MON 
ABSORBING THE REMNANTS OF THIS WARM FRONT. THE MERGED FRONT WILL 
EXTEND FROM APALACHICOLA FLORIDA TO THE CENTRAL BAY OF CAMPECHE 
LATE TUE THEN STALL FROM CENTRAL FLORIDA TO THE CENTRAL BAY OF 
CAMPECHE ON WED AND THU. HIGH PRESSURE WILL BUILD S ACROSS THE 
GULF N OF THE FRONT ON THU. 

CARIBBEAN SEA...                                              
THE UPPER RIDGE COVERS THE NW CARIBBEAN W OF 80W AND EXTENDS A 
RIDGE AXIS NE ACROSS W CUBA TO OVER THE W ATLC. A CUT OFF UPPER 
LOW COVERS THE REMAINDER OF THE CARIBBEAN CENTERED S OF PUERTO 
RICO NEAR 15N68W. A SURFACE TROUGH IS ANALYZED FROM 19N54W 
ACROSS THE VIRGIN ISLANDS/PUERTO RICO TO 14N66W. SCATTERED TO 
HEAVY SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 15N-18N BETWEEN 
60W-70W INCLUDING PUERTO RICO...VIRGIN AND LEEWARD ISLANDS. 
EASTERLY TRADE WINDS ARE USHERING IN SOME ISOLATED LOW LEVEL 
SHOWERS MAINLY FROM 12N-18N BETWEEN 62W-80W. THESE SAME TRADE 
WINDS ARE BANKING LOW CLOUDS WITH ISOLATED SHOWERS INLAND AND 
WITHIN 45 NM ALONG THE COAST OF W PANAMA AND COSTA RICA AND IN 
THE GULF OF HONDURAS S OF 18N W OF 85W. W ATLC SURFACE RIDGE 
WILL SUPPORT A TIGHT PRESSURE GRADIENT ACROSS THE CARIBBEAN E OF 
82W THROUGH THU AND WILL WEAKEN SLIGHTLY ON WED AND THU.

HISPANIOLA...                                                   
CURRENTLY POSSIBLE ISOLATED SHOWERS ARE ALONG THE N COAST OF THE 
DOMINICAN REPUBLIC. NO SIGNIFICANT RAINS ARE EXPECTED TODAY. THE 
UPPER LOW S OF PUERTO RICO WILL SHIFT W BRINGING AN INCREASE IN 
SHOWERS TO THE DOMINICAN REPUBLIC AND S HAITI TONIGHT THROUGH 
MIDWEEK.

ATLANTIC OCEAN...                                               
THE UPPER RIDGE OVER THE CARIBBEAN EXTENDS A RIDGE AXIS ACROSS W 
CUBA NEAR 22N81W THEN OVER THE N BAHAMA ISLANDS TO BEYOND 
BERMUDA. A SURFACE RIDGE COVERS THE W ATLC W OF 50W ANCHORED BY 
A 1027 MB HIGH JUST S OF BERMUDA NEAR 30N66W. AN UPPER TROUGH 
EXTENDS FROM AN UPPER LOW IN THE CENTRAL ATLC NEAR 32N37W ALONG 
25N40W TO 20N56W SUPPORTING GALE CENTER DESCRIBED IN THE SPECIAL 
FEATURES ABOVE AND AN OCCLUDED FRONTAL BOUNDARY. SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ASSOCIATED WITH THE 
UPPER TROUGH ARE WITHIN 175 NM OF LINE FROM 24N40W TO BEYOND 
32N33W. THE COLD FRONT ENTERS THE E ATLC NEAR 32N28W AND EXTENDS 
TO 23N34W WHERE IT BECOMES STATIONARY TO 16N47W. SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 120 NM E 
OF THE COLD FRONT AND WITHIN 75 NM OF LINE FROM 18N37W TO TO 
23N28W. A WEAK SURFACE RIDGE COVERS THE REMAINDER OF THE E ATLC 
N OF 20N E OF 25W ANCHORED BY A 1027 MB HIGH OVER PORTUGAL. THE 
W ATLC SURFACE HIGH WILL SHIFT NE OF THE AREA ON MON NIGHT WITH 
A SURFACE RIDGE EXTENDING SW TO CENTRAL FLORIDA. THE RIDGE WILL 
THEN SHIFT E ON TUE NIGHT ALLOWING A WEAK COLD FRONT TO MOVE 
INTO THE FAR W ATLC. THE COLD FRONT WILL THEN DRIFT E REACHING 
FROM 32N76W TO MELBOURNE FLORIDA ON WED NIGHT AND ACCELERATE 
REACHING FROM BERMUDA TO THE STRAITS OF FLORIDA ON THU NIGHT.

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

$$ 
PAW