000
AXNT20 KNHC 130547 RRA
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SAT JUN 13 2009

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...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0445 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS ALONG 60W/61W S OF 16N MOVING W 10-15 KT. WAVE IS 
EMBEDDED WITHIN DRIER AIR THAN OVER THE PAST COUPLE OF DAYS AS IT 
MOVES ACROSS THE LESSER ANTILLES. SCATTERED SHOWERS AND POSSIBLE 
ISOLATED THUNDERSTORMS ARE WITHIN 45 NM OF LINE FROM 14N63W ACROSS 
THE WINDWARD ISLANDS TO 9N57W. 

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 9N12W 7N21W 3N33W 2N40W 1N52W. 
CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 5N-11N 
BETWEEN 10W-16W INCLUDING THE COAST FROM LIBERIA TO GUINEA. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 4N-9N BETWEEN 
18W-22W AND WITHIN 60 NM ALONG THE THE ITCZ AXIS FROM 22W-29W. 
SCATTERED MODERATE CONVECTION IS WITHIN 60 NM S OF THE ITCZ AXIS 
FROM 45W-47W. 

...DISCUSSION...

GULF OF MEXICO...
A 1015 MB HIGH REMAINS NEARLY STATIONARY OVER THE E GULF NEAR 
27N87W KEEPING WINDS LIGHT ACROSS THE AREA. THE GULF IS DOMINATED BY 
FAIR WEATHER AGAIN TONIGHT WITH HIGH DEBRIS CLOUDS MOVING OFF TEXAS 
AND W LOUISIANA OVER THE NW GULF. THE BROAD UPPER RIDGE REMAINS 
ANCHORED OVER W/CENTRAL MEXICO DOMINATING THE UPPER PATTERN OVER THE 
GULF. LITTLE CHANGE IN THIS PATTERN IS EXPECTED OVER THE WEEKEND AND 
THROUGH THE FIRST OF NEXT WEEK. 

CARIBBEAN SEA...
A SURFACE TROUGH REMAINS IN THE W CARIBBEAN EXTENDING FROM 21N83W TO 
NEAR 11N81W. AN UPPER TROUGH EXTENDS FROM THE W ATLC ACROSS CUBA AND 
OVER THE NW CARIBBEAN N OF 15N W OF 77W TO INLAND OVER CENTRAL 
AMERICA AND THE YUCATAN GENERATING SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS INLAND AND WITHIN 60 NM ALONG THE S COAST OF CUBA 
BETWEEN 78W-84W. A BROAD UPPER RIDGE DOMINATES THE REMAINDER OF THE 
CARIBBEAN DRAWING UPPER LEVEL MOSITURE OVER THE CENTRAL CARIBBEAN 
AND PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS FROM 16N-20N BETWEEN 70W-81W AND SIMILAR 
ACTIVITY S OF 14N TO INLAND OVER COLOMBIA AND PANAMA BETWEEN 
70W-80W. ISOLATED SHOWERS S OF 14N W OF 80W TO INLAND OVER COSTA 
RICA AND NICARAGUA. A TROPICAL WAVE IS GENERATING THE ACTIVITY OVER 
THE WINDWARD ISLANDS...SEE ABOVE. 

ATLANTIC OCEAN...
AN UPPER TROUGH EXTENDS FROM AN UPPER LOW IN THE W ATLC NEAR 27N72W 
ACROSS CUBA INTO THE NW CARIBBEAN GENERATING A SMALL AREA OF 
SHOWERS/THUNDERSTORMS WITHIN A 60 NM RADIUS OF 26.5N74.5W. THE BROAD 
UPPER RIDGE FROM THE CARIBBEAN EXTENDS OVER THE REMAINDER OF THE 
W/CENTRAL ATLC PROVIDING DIFFLUENCE ALOFT AND CONTINUES TO 
GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS 
WITHIN 175 NM OF LINE FROM 29N66W TO OVER THE GREATER ANTILLES NEAR 
20N73W. A BROAD SURFACE RIDGE DOMINATES THE REMAINDER OF THE ATLC 
ANCHORED BY A PAIR OF 1025 MB HIGHS CENTERED NEAR 29N53W AND 27N42W 
GIVING THE REMAINDER OF THE AREA FAIR WEATHER AGAIN TONIGHT. 

$$
WALLACE