000
AXNT20 KNHC 281105
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT APR 28 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1045 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 5N9W 3N20W 2N30W 1N40W 1N50W.  
ISOLATED MODERATE CONVECTION IS FROM EQ-5N BETWEEN 21W-33W.  
SCATTERED MODERATE CONVECTION IS OFF THE COAST OF BRAZIL FROM 
1N-4N BETWEEN 47W-51W.  

...DISCUSSION...

GULF OF MEXICO...
A SLOW MOVING DISSIPATING COLD FRONT EXTENDS FROM THE FLORIDA NE 
COAST TO THE SE GULF OF MEXICO ALONG 31N79W 27N82W 25N86W.  
ISOLATED SHOWERS ARE WITHIN 30 NM OF THE FRONT.  A 1022 MB HIGH 
IS OFF THE COAST OF LOUISIANA NEAR 28N89W PRODUCING 10-15 KT 
ANTICYCLONIC WINDS OVER THE NRN GULF OF MEXICO.  IN THE UPPER 
LEVELS... AN UPPER LEVEL RIDGE NOW DOMINATES THE ENTIRE GULF OF 
MEXICO.   BROKEN HIGH CLOUDS AND SIGNIFICANT UPPER LEVEL 
MOISTURE COVERS THE GULF N OF 24N.  STRONG SUBSIDENCE REMAINS 
OVER THE BAY OF CAMPECHE...THE YUCATAN PENINSULA...AND CUBA.  
EXPECT THE UPPER LEVEL RIDGE TO FLATTEN OUT OVER THE NEXT 24 
HOURS AND PRODUCE WLY UPPER LEVEL FLOW.  ALSO EXPECT THE SURFACE 
COLD FRONT TO COMPLETELY DISSIPATE DURING THE NEXT 6 HOURS.  
THE GFS MODEL ALSO PREDICTS MOISTURE FROM THE NW CARIBBEAN WILL 
ADVECT OVER TO THE ERN BAY OF CAMPECHE AND PRODUCE CONVECTION 
WITHIN 24 HOURS.  

CARIBBEAN SEA...
AN AREA OF RAIN AND SHOWERS CONTINUES OVER HISPANIOLA MAINLY DUE 
TO OROGRAPHIC LIFTING OF THE TRADES.   SCATTERED MODERATE 
CONVECTION IS NOTED ALONG THE COAST OF PANAMA FROM 9N-11N 
BETWEEN 80W-83W.  SIMILAR CONVECTION IS INLAND OVER S MEXICO 
FROM 15N-17N BETWEEN 93W-94W.  THE REMAINDER OF THE CARIBBEAN 
SEA HAS MODERATE TRADES WITH PATCHES OF SHOWERS MOSTLY E OF 
80W.  IN THE UPPER LEVELS...A SHALLOW TROUGH IS OVER ERN CUBA N 
OF 20N.  THE REMAINDER OF THE CARIBBEAN IS UNDER THE INFLUENCE 
OF AN E/W UPPER LEVEL RIDGE WITH AXIS ALONG 10N BETWEEN TRINIDAD 
AND COSTA RICA...PRODUCING WLY UPPER LEVEL FLOW N OF 10N.  
EXPECT MORE RAIN AND SHOWERS OVER THE CENTRAL AND WRN CARIBBEAN 
TO INCLUDE CENTRAL AMERICA DURING THE NEXT 24 HOURS DUE TO THE 
TRADES. 

ATLANTIC...
A 1028 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 39N48W AND 
DOMINATES THE ENTIRE BASIN.  ANOTHER 1024 MB HIGH IS OVER THE E 
ATLANTIC NEAR 35N18W.  MOSTLY ELY SURFACE FLOW WITH FAIR WEATHER 
IS NOTED ACROSS THE ATLANTIC FROM 10N-25N FROM AFRICA TO THE 
CARIBBEAN SEA.  IN THE UPPER LEVELS... A SHARP TROUGH IS OVER 
THE W ATLANTIC N OF 20N BETWEEN 70W-80W.  A RIDGE IS FURTHER E 
BETWEEN 63W-70W N OF 20N.  A TROUGH IS OVER THE CENTRAL ATLANTIC 
N OF 20N BETWEEN 45W-63W.  AN UPPER LEVEL LOW IS EMBEDDED WITHIN 
THE TROUGH NEAR 25N61W.   ISOLATED SHOWERS ARE JUST N OF THE 
CENTER FROM 25N-28N BETWEEN 60W-65W.  A BROAD RIDGE IS OVER THE 
E ATLANTIC N OF 20N E OF 45W.  AN UPPER LEVEL LOW IS CENTERED 
OVER THE TROPICAL ATLANTIC NEAR 14N42W.  CYCLONIC FLOW IS FROM 
5N-20N BETWEEN 30W-50W. 

$$
FORMOSA