000
AXNT20 KNHC 180438
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SUN JUN 18 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0415 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 19W S OF 15N MOVING W 15-20 KT. BROAD 
LEVEL CIRCULATION IS OBSERVED ON INFRARED SATELLITE IMAGERY. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 75 NM OF 
LINE 8N16W-4N21W. 

TROPICAL WAVE IS ALONG 47W S OF 18N MOVING W 15-20 KT. BROAD 
LOW/MID LEVEL CURVATURE SIGNATURE IS OBSERVED ON INFRARED 
SATELLITE IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS FROM 
10N-13N BETWEEN 43W-49W.  

TROPICAL WAVE IS ALONG 65W S OF 23N MOVING W 15-20 KT. WAVE 
SIGNATURE CURVATURE HAS DIMINISHED AS IT CROSSED INTO THE E 
CARIBBEAN. WAVE IS BENEATH THE WESTERN EDGE OF AN UPPER RIDGE 
BUT IS ONLY PRODUCING ISOLATED SHOWERS OVER THE AREA S OF 18N 
FROM 68W TO OVER THE LESSER ANTILLES. 

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 11N14W 5N25W 6N37W 10N45W 6N50W 
5N55W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS N OF 2N 
TO INLAND OVER SW AFRICA FROM 6W-10W. CLUSTERS OF SIMILAR 
CONVECTION ARE WITHIN 200 NM OF THE AXIS FROM 20W-40W. CLUSTERS 
OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM OF THE AXIS 
FROM 47W-57W. 

...DISCUSSION...
GULF OF MEXICO...
MID/UPPER LEVEL TROUGH REMAINS OVER THE CENTRAL US INTO TEXAS 
AND THE NW GULF N OF 25N W OF 91W. THE DEEP LAYERED TROUGH THAT 
WAS IN THE W ATLC HAS RETROGRADED TO INCLUDE THE E GULF TONIGHT 
N OF 22N E OF 85W. THIS LEAVES THE REMAINDER OF THE GULF UNDER 
AN UPPER HIGH LOCATED NEAR 23N90W WITH A SHARP RIDGE AXIS 
EXTENDING N OVER THE MISSISSIPPI VALLEY. THE GULF IS FOR THE 
MOST PART QUIET TONIGHT WITH THE EXCEPTION OF DIMINISHING 
AFTERNOON THUNDERSTORMS AND ISOLATED SHOWERS OVER THE SE GULF S 
OF 26N E OF 83W THROUGH THE STRAITS OF FLORIDA. 

CARIBBEAN SEA...
THE CARIBBEAN IS DOMINATED BY TWO UPPER HIGHS...THE ONE OVER THE 
GULF OF MEXICO AND THE SECOND OVER THE W TROPICAL ATLC. BROAD 
UPPER TROUGH OVER THE W ATLC DIPS INTO THE CENTRAL CARIBBEAN N 
OF 15N FROM 65W-85W. CLUSTERS OF SHOWERS/THUNDERSTORMS ARE AT 
THE BASE OF THE UPPER TROUGH EXTENDING ACROSS THE N CARIBBEAN N 
OF 18N FROM PUERTO RICO THROUGH CUBA. DRY AIR CONTINUES TO 
DOMINATE MOST OF THE CARIBBEAN WITH THE EXCEPTION OF TROPICAL 
MOISTURE BEING ADVECTED ACROSS THE E CARIBBEAN AND THE SHOWERS 
ASSOCIATED WITH THE TROPICAL WAVE. 

ATLANTIC OCEAN...
BROAD DEEP LAYERED TROUGH CONTINUES TO DIG S ACROSS THE W ATLC 
INTO THE GULF OF MEXICO AND THE N CENTRAL CARIBBEAN FROM W OF 
60W. THE ASSOCIATED SURFACE TROUGH EXTENDS THROUGH 32N63W SW TO 
27N69W. DESPITE THE INFLUX OF DRY AIR...CLUSTERS OF SHOWERS/ 
THUNDERSTORMS ARE AT THE BASE OF THE UPPER TROUGH S OF 25N FROM 
60W-83W. NARROW RIDGE AXIS IS BETWEEN THE W ATLC TROUGH AND A 
BROAD UPPER LOW CENTERED NEAR 30N35W WITH THE UPPER TROUGH 
EXTENDING S TO 20N35W. AT THE SURFACE...BROAD HIGH PRESSURE 
DOMINATES THE ATLC N OF 15N E OF 60W ANCHORED BY A 1035 MB HIGH 
WELL N OF THE REGION. THE DEEP TROPICS IS DOMINATED BY AN UPPER 
HIGH OVER THE W ATLC NEAR 15N49W AND A SECOND RIDGE EXTENDING 
OFF THE AFRICAN COAST ALONG 15N/16N E OF 30W. DIFFLUENCE ON THE 
W SIDE OF THE UPPER HIGH IN THE W TROPICAL ATLC IS GENERATING AN 
AREA OF OVERCAST CLOUDINESS WITH SCATTERED SHOWERS/ISOLATED 
THUNDERSTORMS FROM 17N-28N BETWEEN 50W-60W. 

$$
WALLACE