000
AXNT20 KNHC 081742
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 PM EDT MON APR 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.

...ITCZ/MONSOON TROUGH... 

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 05N09W TO 
03N17W TO 01N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS 
EXTENDS FROM 01N20W TO THE EQUATOR TO 29W. WIDELY SCATTERED 
MODERATE CONVECTION IS FROM THE EQUATOR TO 06N BETWEEN 02W-20W.

...DISCUSSION...

GULF OF MEXICO...                                          
MOSTLY MIDDLE TO UPPER LEVEL RIDGING AND SOUTHWESTERLY FLOW 
ALOFT DOMINATES OVER THE GULF BASIN THIS AFTERNOON. THIS 
ATMOSPHERIC REGIME CONTINUES TO SUPPORT STABLE CONDITIONS AT THE 
SURFACE AS THE WESTERN PERIPHERY OF HIGH PRESSURE ANCHORED 
ACROSS THE SW NORTH ATLC PROVIDES SUSTAINED SOUTHEAST WINDS IN 
THE RANGE OF 10 TO 20 KT. THE HIGHER END OF THOSE WIND SPEEDS 
ARE NOTED GENERALLY W OF 90W AS AN AREA OF LOW PRESSURE DEVELOPS 
ACROSS THE CENTRAL AND SOUTHERN U.S. PLAINS DUE TO AN INCREASED 
PRESSURE GRADIENT. WITH DEVELOPING LOW PRESSURE TRACKING NE 
TOWARDS THE GREAT LAKES REGION WEDNESDAY INTO THURSDAY AND HIGH 
PRESSURE REMAINING NEARLY STATIONARY ACROSS THE SW NORTH 
ATLC...THE SOUTHERLY WINDS ARE FORECAST TO PERSIST UNTIL THE 
ASSOCIATED COLD FRONT EMERGES OFF THE TEXAS AND LOUISIANA COASTS 
EARLY THURSDAY.

CARIBBEAN SEA...                                            
ZONAL WESTERLY MIDDLE TO UPPER LEVEL FLOW DOMINATES OVER THE 
CARIBBEAN WITH WATER VAPOR IMAGERY INDICATING MOSTLY DRY AIR AND 
SUBSIDENCE PROVIDING OVERALL STABLE CONDITIONS AND FAIR SKIES 
THIS AFTERNOON. TRADES CONTINUE TO PERSIST IN THE RANGE OF 15 TO 
25 KT WITH THE STRONGEST OF THESE WINDS NOTED GENERALLY S OF 15N 
BETWEEN 67W-78W...AND IN CLOSE PROXIMITY TO THE COAST OF 
COLOMBIA. THIS SYNOPTIC SETUP IS EXPECTED TO LAST THROUGH MUCH 
OF THE WEEK AHEAD AS HIGH PRESSURE WILL REMAIN ANCHORED ACROSS 
THE SW NORTH ATLC AND WILL BE SLOW TO DRIFT EASTWARD.

ATLANTIC OCEAN...                                            
WHILE ZONAL WESTERLY FLOW DOMINATES IN THE UPPER LEVELS W OF 
60W...WEAK MID-LEVEL RIDGING CONTINUES TO SUPPORT A SURFACE 
RIDGE ANCHORED BY A 1025 MB HIGH CENTERED WEST OF BERMUDA NEAR 
33N70W. THE INFLUENCE FROM THIS HIGH REACHES AS FAR SOUTH AS 24N 
AND REMAINS WEST OF A COLD FRONT ANALYZED FROM 32N51W TO 25N60W. 
A STATIONARY FRONT THEN CONTINUES WEST-SOUTHWEST TO THE SE 
BAHAMAS NEAR 22N76W. ISOLATED SHOWERS ARE OCCURRING WITHIN 120 
NM EITHER SIDE OF THE BOUNDARIES WHICH ARE SUPPORTED ALOFT BY A 
MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH WITH AXIS ALONG 56W. THE 
FRONT IS FORECAST TO CONTINUE DRIFTING EASTWARD INTO THE CENTRAL 
ATLC AS THE AFOREMENTIONED SURFACE HIGH REMAINS ANCHORED IN THE 
VICINITY OF BERMUDA AND STRETCHES ITS INFLUENCE FROM 45W TO THE 
SOUTHEAST U.S. COAST BY LATE TUESDAY. THE REMAINDER OF THE 
EASTERN ATLC IS UNDER THE INFLUENCE OF ANOTHER SURFACE RIDGE 
ANCHORED BY A 1026 MB HIGH CENTERED NEAR 30N36W. A WEAKENING 
SURFACE TROUGH REMAINS EMBEDDED WITHIN THE RIDGING ANALYZED FROM 
24N22W TO 30N24W BUT PROVIDES LITTLE SENSIBLE WEATHER. 

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

$$
HUFFMAN