000
AXNT20 KNHC 151044
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL 
805 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...ITCZ/MONSOON TROUGH... 

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 09N14W TO 
05N14W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
05N14W TO 02N19W TO 02N26W TO THE EQUATOR NEAR 29W. ISOLATED 
MODERATE CONVECTION IS FROM THE EQUATOR TO 05N BETWEEN 10W AND 
34W.

...DISCUSSION...

GULF OF MEXICO...                                               
A WEAKENING MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON 
WATER VAPOR IMAGERY OVER THE SE CONUS AND EASTERN GULF WITH AXIS 
FROM 33N79W TO A BASE NEAR 24N88W. WHILE MID-LEVEL DIFFLUENCE IS 
MAXIMIZED OVER FLORIDA AND PORTIONS OF THE SW NORTH ATLC...A 
WARM FRONT CONTINUES TO PROVIDE FOCUS FOR LOW-LEVEL MOISTURE 
CONVERGENCE AND SCATTERED SHOWERS AND TSTMS N OF 26N W OF 88W. 
THE FRONT IS ANALYZED FROM 32N81W TO 30N86W TO 30N92W AND IS 
EXPECTED TO CONTINUE GRADUALLY LIFTING NORTH OF 30N OVER THE 
NEXT FEW HOURS AND EVENTUALLY WEAKEN OVER PORTIONS OF THE SW 
NORTH ATLC TUESDAY INTO WEDNESDAY. THE REMAINDER OF THE GULF IS 
DOMINIATED BY SOUTH-SOUTHEASTERLY RETURN FLOW THAT IS FORECAST 
TO PERSIST THROUGH 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 EARLY 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 12N78W. 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 66W-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 60W. UPPER LEVEL DIFFLUENCE IS 
MAXIMIZED EAST OF THE TROUGH AXIS AND IS GENERATING SCATTERED 
SHOWERS AND TSTMS N OF 27N BETWEEN 73W-80W. THE REMAINDER OF THE 
SW NORTH ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED 
BY A 1023 MB HIGH CENTERED NEAR 27N52W. ANOTHER 1023 MB HIGH 
ALSO INFLUENCES THE CENTRAL AND EASTERN ATLC WITH GENERALLY FAIR 
WEATHER THAT EXTENDS AN AXIS FROM THE HIGH CENTER NORTHEASTWARD 
TO A 1024 MB HIGH CENTERED NW OF THE MADEIRA ISLANDS NEAR 32N23W.

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

$$
HUFFMAN