000
AXNT20 KNHC 150543
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 AM EDT MON APR 15 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...ITCZ/MONSOON TROUGH... 

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N13W TO 
06N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
06N16W TO THE EQUATOR NEAR 29W. WIDELY SCATTERED MODERATE 
CONVECTION IS FROM THE EQUATOR TO 05N BETWEEN 14W AND 31W.

...DISCUSSION...

GULF OF MEXICO...                                               
A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR 
IMAGERY OVER THE SE CONUS AND CENTRAL GULF WITH AXIS FROM 34N85W 
TO A BASE NEAR 22N92W. WHILE MID-LEVEL DIFFLUENCE IS MAXIMIZED 
OVER THE NE GULF AND PORTIONS OF NORTHERN FLORIDA...A WARM FRONT 
CONTINUES TO PROVIDE FOCUS FOR LOW-LEVEL MOISTURE CONVERGENCE 
AND SCATTERED SHOWERS AND TSTMS N OF 26N W OF 89W. THE FRONT IS 
EXPECTED TO CONTINUE GRADUALLY LIFTING NORTH-NORTHEASTWARD 
THROUGH THE OVERNIGHT HOURS INTO MONDAY AND EVENTUALLY WEAKEN 
OVER PORTIONS OF THE SW NORTH ATLC TUESDAY INTO WEDNESDAY. FOR 
THE REMAINDER OF THE GULF ONCE THE FRONT LIFTS NORTH OF THE 
BASIN...SOUTH-SOUTHEASTERLY RETURN FLOW IS FORECAST TO PERSIST 
LATE THURSDAY AS AN AREA OF LOW PRESSURE DEVELOPS OVER THE FOUR 
CORNERS REGION AND EJECTS NORTHEASTWARD ACROSS THE CENTRAL 
PLAINS TOWARDS THE GREAT LAKES REGION. THE ASSOCIATED COLD FRONT 
IS EXPECTED TO EMERGE OFF THE TEXAS AND LOUISIANA COAST BY LATE 
THURSDAY INTO FRIDAY.
 
CARIBBEAN SEA...                                                
A MIDDLE TO UPPER LEVEL RIDGE REMAINS ANCHORED OVER THE 
CARIBBEAN SEA BY AN ANTICYCLONIC CIRCULATION CENTERED OVER THE 
SW CARIBBEAN NEAR 10N76W. WATER VAPOR IMAGERY INDICATES DRY AIR 
AND OVERALL SUBSIDENCE CONTINUES TO PROVIDE FOR STABLE 
CONDITIONS AT THE SURFACE. TRADES PERSIST UNDER THESE FAIR 
CONDITIONS IN THE RANGE OF 15 TO 25 KT WITH THE HIGHEST WINDS 
GENERALLY OCCURRING S OF 16N BETWEEN 65W-78W...AND IN CLOSE 
PROXIMITY TO THE COAST OF COLOMBIA. THIS OVERALL SYNOPTIC 
PATTERN IS EXPECTED TO PERSIST THROUGH MUCH OF THE WEEK AHEAD.

ATLANTIC OCEAN...                                               
AN APPROACHING MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED 
ON WATER VAPOR IMAGERY OVER THE SE CONUS AND NE GULF OF 
MEXICO...HOWEVER MIDDLE TO UPPER LEVEL RIDGING STILL HOLDS IN 
PLACE OVER THE SW NORTH ATLC W OF 65W. UPPER LEVEL DIFFLUENCE IS 
MAXIMIZED EAST OF THE TROUGH AXIS AND IS GENERATING SCATTERED 
SHOWERS AND TSTMS N OF 27N BETWEEN 76W-81W...GENERALLY REMAINING 
OFF THE FLORIDA PENINSULA COAST. THE REMAINDER OF THE SW NORTH 
ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 
1024 MB HIGH CENTERED NEAR 27N52W. THIS HIGH ALSO INFLUENCES THE 
CENTRAL ATLC WITH GENERALLY FAIR WEATHER AND EXTENDS AN AXIS 
FROM THE HIGH CENTER EASTWARD TO 28N40W TO A 1027 MB HIGH 
CENTERED WEST OF THE MADEIRA ISLANDS NEAR 32N23W.

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

$$
HUFFMAN