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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 070004
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST FRI DEC 06 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...SPECIAL FEATURE...                                           

A 1000 MB SURFACE LOW LOCATED OVER THE CENTRAL ATLANTIC NEAR 
34N42W IS PRODUCING GALE-FORCE WINDS FROM 27N TO BEYOND 31N 
BETWEEN 43W-52W. NW TO N WINDS 30-35 KT WITH SEAS 11-16 FT IN 
MERGING NE AND NW SWELL ARE FORECAST FOR THE NEXT 24 HOURS. 
PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC 
...FOR MORE DETAILS. 

...ITCZ/MONSOON TROUGH...                                     

THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE TROPICAL 
ATLC NEAR 7N13W TO 7N17W WHERE THE ITCZ BEGINS AND CONTINUES TO 
4N30W TO 3NN42W. CLUSTERS OF SCATTERED SHHOWERS ARE FROM 1N-7N 
BETWEEN 25W-40W. 

...DISCUSSION...

GULF OF MEXICO...                                                

AS OF 2100 UTC...A STRONG COLD FRONT IS OVER THE W GULF OF 
MEXICO FROM SE LOUISIANA NEAR 29N91W TO S OF TAMPICO MEXICO NEAR 
20N97W. OVERCAST COLD AIR STRATOCUMULUS CLOUDS ARE NW OF THE 
FRONT. A CONSIDERABLE AMOUNT OF COLD AIR ADVECTION IS ASSOCIATED 
WITH THE FRONT. RADAR IMAGERY SHOWS SCATTERED SHOWERS ALONG THE 
COAST OF LOUISIANA FROM 28N-30N BETWEEN 90W-93W. 25 KT NORTHERLY 
WINDS ARE N OF THE FRONT WHILE 10-20 KT SOUTHERLY WINDS ARE OVER 
THE REMAINDER OF THE GULF OF MEXICO WITH FAIR WEATHER. IN THE 
UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE GULF WITH AXIS 
ALONG 83W. STRONG SUBSIDENCE IS OVER THE ENTIRE GULF. EXPECT IN 
24 HOURS FOR THE COLD FRONT TO EXTEND FROM THE FLORIDA PANHANDLE 
TO THE BAY OF CAMPECHE WITH SHOWERS IN THE THE BAY OF CAMPECHE. 
ALSO EXPECT THE UPPER LEVEL RIDGE AXIS TO SHIFT E TO 78W. 

CARIBBEAN SEA...                                              

15-25 KT TRADEWINDS ARE OVER THE CARIBBEAN SEA AND CENTRAL 
AMERICA WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA.  
SCATTERED SHOWERS ARE OVER THE HIGHER ELEVATIONS OF PUERTO 
RICO...HISPANIOLA...JAMAICA...HONDURAS...AND NICARAGUA. A 
MONSOON TROUGH EXTENDS FROM N COLOMBIA AT 7N77W TO BEYOND W 
COSTA RICA AT 9N85W. ISOLATED MODERATE CONVECTION IS WITHIN 120 
NM OF THE TROUGH. ELSEWHERE...ISOLATED MODERATE CONVECTION IS 
OVER THE LEEWARD ISLANDS N OF 16N E OF 63W DUE TO A SHEAR LINE.  
IN THE UPPER LEVELS... UPPER LEVEL RIDGING IS OVER THE W 
CARIBBEAN W OF 74W. AN UPPER LEVEL TROUGH IS OVER THE E 
CARIBBEAN WITH AN EMBEDDED UPPER LEVEL LOW OVER THE LEEWARD 
ISLANDS NEAR 19N62W. STRONG SUBSIDENCE IS OVER MOST OF THE 
CARIBBEAN SEA W OF 64W. CONSIDERABLE UUER LEVEL MOISTURE IS OVER 
THE LEEWARD ISLANDS. EXPECT LITTLE CHANGE OVER THE NEXT 24 
HOURS. 

HISPANIOLA...                    

PRESENTLY SCATTERED SHOWERS ARE OVER THE HIGHER ELEVATIONS OF  
HISPANIOLA. STRONG UPPER LEVEL SUBSIDENCE IS HOWEVER SUPPRESSING 
THE FORMATION OF THUNDERSTORMS. EXPECT OVER THE NEXT 24 HOURS 
FOR MORE SCATTERED SHOWERS TO ADVECT OVER HISPANIOLA FROM THE 
EAST. 

ATLANTIC OCEAN...                                               

A 1028 MB HIGH IS CENTERED OVER THE W ATLANTIC NEAR 33N62W. A 
1000 MB GALE LOW IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 
34N42W. A COLD FRONT EXTENDS FROM 31N38W TO 24N44W TO 21N53W. A 
SHEAR LINE CONTINUES TO THE LEEWARD ISLANDS AT 19N60W. SCATTERED 
SHOWERS WITH ISOLATED THUNDERSTORMS ARE WITHIN 90 NM OF THE 
FRONT AND SHEAR LINE. ANOTHER 1001 MB GALE LOW IS CENTERED OVER 
THE E ATLANTIC NEAR 35N27W. IN THE UPPER LEVELS...AN UPPER LEVEL 
LOW IS OVER THE CENTRAL ATALNTIC NEAR 34N41W SUPPORTING THE 
CENTRAL ATLANTIC SURFACE FRONT. LIKEWISE AN UPPER LEVEL LOW IS 
CENTERED OVER NEAR 37N26W SUPPORTING THE E ATLANTIC LOW. EXPECT 
OVER THE NEXT 24 HOURS FOR THE CENTRAL ATLANTIC FRONT TO MOVE E 
WITH CONVECTION...WHILE THE E ATLANTIC LOW REMAINS QUASI-
STATIONARY AND WEAKENS. 

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

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FORMOSA