000
AXNT20 KNHC 190611
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT SUN MAR 18 2007

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 5N9W 3N20W 2N40W 2N50W.  SCATTERED 
STRONG CONVECTION IS ALONG THE COAST OF W AFRICA FROM EQ-7N 
BETWEEN 8W-12W.  SCATTERED MODERATE CONVECTION IS FROM 2N-5N 
BETWEEN 16W-20W...AND FROM 1N-4N BETWEEN 24W-28W.  SCATTERED 
SHOWERS ARE FROM 1N-3N BETWEEN 38W-45W.   

...DISCUSSION...

GULF OF MEXICO...
A 1025 MB HIGH IS CENTERED OVER S GEORGIA.  15-20 KT E TO SE 
RETURN FLOW DOMINATES THE ENTIRE GULF OF MEXICO.  NIGHT CHANNEL 
SATELLITE IMAGERY SHOWS MOSTLY FAIR WEATHER OVER THE GULF.  IN 
THE UPPER LEVELS... WLY ZONAL FLOW WITH STRONG SUBSIDENCE COVERS 
THE ENTIRE GULF.  AN AREA OF UPPER LEVEL MOISTURE AND BROKEN 
HIGH CLOUDS IS OVER TEXAS MOVING E TOWARDS THE NW GULF.  EXPECT 
LITTLE CHANGE OVER THE NEXT 24 HOURS OTHER THAN SURFACE 
TEMPERATURES GRADUALLY WARMING.    
 
CARIBBEAN...
THE TAIL END OF A FRONTAL TROUGH EXTENDS FROM HISPANIOLA TO THE 
CENTRAL CARIBBEAN ALONG 20N72W 16N78W.  SCATTERED SHOWERS ARE 
OVER HISPANIOLA AND WITHIN 60 NM EITHER SIDE OF THE TROUGH.  
SCATTERED SHOWERS ARE ALSO INLAND...ESPECIALLY OVER HIGHER 
ELEVATIONS...OVER CENTRAL AMERICA FROM COSTA RICA TO BELIZE 
MOVING W WITH THE TRADES.  ISOLATED SHOWERS ARE OVER THE LEEWARD 
AND WINDWARD ISLANDS E OF 67W ALSO MOVING W WITH THE TRADES.  IN 
THE UPPER LEVELS... WLY FLOW IS OVER CENTRAL AMERICA AND THE W 
CARIBBEAN W OF 80W.  A RIDGE IS OVER THE REMAINDER OF THE 
CARIBBEAN SEA WITH RIDGE AXIS ALONG 63W.  STRONG SUBSIDENCE IS 
OVER THE CARIBBEAN SEA EXCEPT OVER HISPANIOLA AND NRN SOUTH 
AMERICA.  EXPECT THE FRONTAL TROUGH TO ADVECT OUT OF THE CENTRAL 
CARIBBEAN SEA OVER THE NEXT 24 HOURS WITH TRADEWIND SHOWERS TO 
CONTINUE.  THE UPPER LEVEL RIDGE WILL ALSO MOVE E INTO THE 
ATLANTIC DURING THE NEXT 24 HOURS LEAVING WLY ZONAL FLOW OVER 
THE ENTIRE SEA.     
 
ATLANTIC...
THE 1025 MB HIGH OVER S GEORGIA PRODUCING NELY SURFACE FLOW OVER 
THE W ATLANTIC W OF 70W WITH BANDS OF BROKEN COLD AIR 
STRATOCUMULUS CLOUDS.  A STATIONARY FRONT IS FURTHER E FROM  
31N60W TO HISPANIOLA NEAR 20N72W.  SCATTERED SHOWERS AND 
ISOLATED THUNDERSTORMS ARE WITHIN 120 NM EITHER SIDE OF THE 
FRONT.  A VERY STRONG SURFACE HIGH IS CENTERED N OF THE AZORES 
ISLANDS NEAR 45N31W.  A RELATIVELY STRONG PRESSURE GRADIENT IS 
FROM 10N-30N BETWEEN 20W-60W PRODUCING STRONGER THAN NORMAL NE 
TO E SURFACE FLOW WITH BROKEN LOW CLOUDS.  IN THE UPPER 
LEVELS... THE BASE OF AN UPPER LEVEL TROUGH IS OVER THE W 
ATLANTIC N OF 25N BETWEEN 60W-80W.  A RIDGE IS OVER THE CENTRAL 
ATLANTIC BETWEEN 50W-60W.  A LARGE TROUGH IS OVER THE E ATLANTIC 
N OF 10N AND E OF 50W.  EXPECT THE STATIONARY FRONT TO REMAIN IN 
PLACE FOR THE NEXT 24 HOURS.  ALSO EXPECT LITTLE CHANGE IN THE 
UPPER LEVELS FOR THE NEXT 24 HOURS.       

$$
FORMOSA