000
AXNT20 KNHC 161724
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SAT APR 15 2006

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 
SECTIONS OF SOUTH AMERICA...AND THE 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 
1700 UTC.

...ITCZ...

ITCZ AXIS IS ALONG 7N11W 2N30W INTO S AMERICA NEAR 3N52W. 
SCATTERED MODERATE TO STRONG CONVECTION IS LOCATED WITHIN A 60 
NM RADIUS OF 2N40W AND FROM 4N TO 6N W OF 48W TO THE S AMERICA 
COAST. 

...DISCUSSION...

GULF OF MEXICO...
WELL-DEFINED ELONGATED MIDDLE/UPPER LEVEL CYCLONIC CIRCULATION 
IS CENTERED ALONG THE SOUTHERN MEXICO COAST NEAR 16N98W. THE 
CIRCULATION IS DRIFTING TO THE NW AND CYCLONIC FLOW COVERS THE 
SW QUARTER OF THE AREA. FLOW BECOMES ANTICYCLONIC OVER THE 
EASTERN HALF OF THE GULF. STRONG WESTERLIES ALOFT COVER THE GULF 
N OF ABOUT 28N. STRONG SUBSIDENCE COVERS NOT ONLY THE ENTIRE 
GULF AND THE SURROUNDING REGION BUT ALSO THE E PACIFIC E OF 
110W. SKIES ARE MOSTLY CLEAR OVER THE AREA EXCEPT FOR SCATTERED 
TO BROKEN LOW CLOUDS ALONG THE TEXAS AND SW LOUISIANA COASTLINES.

CARIBBEAN SEA...
THE FLOW IS PREDOMINATELY ANTICYCLONIC ALOFT OVER MOST OF THE 
REGION EXCEPT OVER THE NE PART. THE SUBSIDENCE NOTED ABOVE 
COVERS THE ENTIRE CARIBBEAN AND IS STRONGEST N OF ABOUT 18N. 
ONLY A FEW SCATTERED SHOWERS ARE MOVING WESTWARD ACROSS THE 
AREA. THE ORIGINS OF A SUBTROPICAL JET ARE OVER THE SE PART NEAR 
15N68W. THE JET CONTINUES NE ACROSS THE LEEWARD ISLANDS OUT INTO 
THE ATLANTIC.

ATLANTIC...
VERY DISTINCT FEATURES ALOFT COVER THE TROPICAL AND SUBTROPICAL 
ATLANTIC. THE FIRST OF THESE IS A LARGE MIDDLE/UPPER LEVEL 
TROUGH THAT HAS ITS AXIS ALONG 62W N OF 20N WITH CYCLONIC FLOW 
LOCATED N OF 20N BETWEEN ABOUT 45W TO 80W. A JET EMERGES OFF OF 
THE UNITED STATES COAST OVER S CAROLINA...DIPS TO 28N65W...AND 
THEN TURNS NE THROUGH 32N56W AND OUT OF THE DISCUSSION AREA. 
FURTHER S IS A STRONG SUBTROPICAL JET THAT EXTENDS THROUGH THE 
LEEWARD ISLAND TO 23N55W TO 28N38W AND THEN DIVES SE THROUGH 
18N25W. STRONGEST FLOW ALONG THE JET IS BETWEEN 45W AND 55W. 
OVER THE DEEP TROPICS A LARGE ANTICYCLONIC CIRCULATION AT THE 
MIDDLE/UPPER LEVELS IS CENTERED NEAR 12N52W. THIS FEATURE 
DOMINATES THE AREA S OF ABOUT 23N W OF 25W. AT THE SURFACE A 
1011 MB LOW IS LOCATED NEAR 27.5N48W...MOVING NE ABOUT 15 KT. A 
COLD FRONT TRAILS SW FROM THE LOW TO 19N60W AND THEN BECOMES A 
TROUGH INTO PUERTO RICO. A PRE-FRONTAL TROUGH IS LOCATED FROM 
24N50W TO 16N60W. DIVERGENCE ALOFT IS AIDING THE FORMATION OF 
BROKEN/OVERCAST LAYERED CLOUDS WITH SCATTERED SHOWERS AND 
THUNDERSTORMS N OF 27N BETWEEN 20W AND 44W. A SURFACE RIDGE OVER 
THE E ATLANTIC IS LOCATED THROUGH 32N27W TO 19N48W. 

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CAB