000
AXNT20 KNHC 180540
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
105 AM EST THU DEC 18 2014

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0530 UTC.

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

THE MONSOON TROUGH CROSSES THE AFRICAN COAST NEAR 08N13W AND 
CONTINUES OVER THE EASTERN ATLANTIC TO NEAR 05N21W. THE ITCZ 
BEGINS AT 05N21W AND CONTINUES TO 03N30W TO 05N45W TO THE COAST 
OF SOUTH AMERICA AT 01N50W. SCATTERED MODERATE CONVECTION IS 
FROM 02N-07N BETWEEN 27W-46W. 
 
...DISCUSSION...

GULF OF MEXICO... 

A FRONTAL SYSTEM TRAVERSES THE BASIN. IT STARTS AS A WARM FRONT 
FROM A 1014 MB LOW CENTERED OVER S TEXAS TO 29N96W TO 25N90W. A 
STATIONARY FRONT IS FROM 25N90W TO 26N85W. A COLD FRONT STARTS 
FROM 26N85W TO 27N82W THEN ACROSS THE FLORIDA PENINSULA INTO THE 
ATLANTIC. ISOLATED SHOWERS ARE ALONG THE COLD FRONT AND BEHIND 
THE STATIONARY FRONT AFFECTING THE N GULF WATERS N OF 27N 
BETWEEN 88W-93W. 5-10 KT NORTHERLY WINDS ARE NOTED ON N OF THE 
FRONT WHILE 10-15 KT E TO SE WINDS ARE S OF THE FRONT. FAIR 
WEATHER PREVAILS THROUGHOUT THE REMAINDER OF THE GULF. AT UPPER 
LEVELS...AN UPPER-LEVEL RIDGE PREVAILS OVER THE GULF WITH AXIS 
ALONG 90W. UPPER-LEVEL MOISTURE IS OVER THE N GULF N OF 26N WITH 
STRONG SUBSIDENCE OVER THE S GULF. EXPECT IN 24 HOURS FOR THE 
FRONTAL SYSTEM TO DISSIPATE AND FOR SCATTERED SHOWERS TO BE 
ALONG THE TEXAS AND NE MEXICO COASTS DUE TO RETURN SE LOW LEVEL 
FLOW. 

CARIBBEAN SEA...   

A DISSIPATING COLD FRONT EXTENDS FROM THE LEEWARD ISLANDS AT 
16N62W TO 15N75. ISOLATED MODERATE CONVECTION REMAINS S OF 
HISPANIOLA FROM 15N-17N BETWEEN 73W-77W. ISOLATED CONVECTION IS 
PRESENT ALONG THIS BOUNDARY. SCATTERED MODERATE CONVECTION IS 
ALONG 81W BETWEEN 10N-19N. AT UPPER LEVELS...AN UPPER-LEVEL 
TROUGH IS OVER THE W CARIBBEAN W OF 80W WITH STRONG SUBSIDENCE. 
ZONAL FLOW PREVAILS OVER THE REMAINDER OF THE CARIBBEAN. EXPECT 
OVER THE NEXT 24 HOURS FOR THE FRONTAL BOUNDARY TO DISSIPATE.
                             
HISPANIOLA...                   

FAIR WEATHER PREVAILS ACROSS THE ISLAND. EXPECT SIMILAR 
CONDITIONS TO PREVAIL OVER THE NEXT 24 HOURS. 

ATLANTIC OCEAN...   

AN UPPER-LEVEL TROUGH WITH AXIS ALONG 63W IS SUPPORTING A COLD 
FRONT EXTENDING FROM THE E GULF ACROSS THE FLORIDA PENINSULA 
INTO THE W ATLANTIC 27N80W TO 33N66W TO 42N64W. ISOLATED 
MODERATE CONVECTION IS BEHIND THE FRONT FROM 27N-30N BETWEEN 76W-
79W. TO THE E...A 1021 MB SURFACE HIGH IS CENTERED NEAR 30N55W. 
ANOTHER UPPER-LEVEL TROUGH WITH AXIS ALONG 50W SUPPORTS A 
FRONTAL BOUNDARY ACROSS THE CENTRAL ATLANTIC. IT STARTS AS A 
COLD FRONT FROM 16N60W TO 26N45W. A STATIONARY FRONT EXTENDS 
FROM 26N45W TO 35N39W. THEN A COLD FRONT CONTINUES FROM THAT 
POINT INTO THE N ATLANTIC. SCATTERED MODERATE CONVECTION IS 
WITHIN 200 NM OF THESE BOUNDARIES N OF 21N BETWEEN 31W-48W. A 
LARGE 1034 MB HIGH IS CENTERED E OF THE AZORES NEAR 40N19W. 
EXPECT THE WESTERN ATLANTIC COLD FRONT TO CONTINUE MOVING E OVER 
THE NEXT 24 HOURS...WHILE THE CENTRAL ATLANTIC FRONT BECOMES 
STATIONARY WITH CONVECTION.
 
FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$

ERA