000
AXNT20 KNHC 191044
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU APR 19 2012

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC NEAR 9N13W ALONG 6N15W TO 3N18W WHERE THE ITCZ AXIS 
CONTINUES ALONG 1N23W 2N30W THEN S OF THE EQUATOR NEAR 39W. 
LARGE CLUSTERS OF SCATTERED STRONG CONVECTION ARE FROM 3N TO 
JUST S OF THE EQUATOR E OF 14W TO THE PRIME MERIDIAN. CLUSTERS 
OF SCATTERED/MODERATE STRONG CONVECTION ARE WITHIN 90 NM OF LINE 
FROM 4N10W 4N17W TO 3N30W.  

...DISCUSSION...

GULF OF MEXICO...
THE UPPER TROUGH OVER THE E CONUS EXTENDS S TO OVER THE GULF 
SUPPORTING A WEAK COLD FRONT AT 19/0900 UTC EXTENDS INTO THE 
GULF FROM A 1012 MB LOW NEAR TALLAHASSEE FLORIDA ALONG 28N84W TO 
26N85W WHERE IT BECOMES STATIONARY TO OVER THE YUCATAN PENINSULA 
DISSIPATING TO N GUATEMALA. CLUSTERS OF ISOLATED SHOWERS/ 
THUNDERSTORMS ARE WITHIN 200 NM E OF THE FRONT TO INLAND OVER 
FLORIDA. STRONG SUBSIDENCE AND DRY STABLE AIR ARE DOMINATING THE 
GULF W OF THE FRONT AS A SURFACE RIDGE CONTINUES TO BUILD S OVER 
THE W GULF ANCHORED BY A 1019 MB HIGH OVER E ARKANSAS GIVING THE 
AREA W OF THE FRONT MOSTLY CLEAR SKIES AGAIN THIS MORNING. THE 
LOW WILL DRIFT NE AS THE FRONT DISSIPATES LATER TODAY. A 
STRONGER COLD FRONT WILL ENTER THE W GULF FRI NIGHT AND REACH 
FROM A LOW OVER SE LOUISIANA TO THE BAY OF CAMPECHE EARLY SAT.  
THE LOW WILL BE IN THE N/CENTRAL GULF ON SUN WITH THE FRONT 
EXTENDING TO THE BAY OF CAMPECHE. THE FRONT IS EXPECTED TO EXIT 
THE AREA ON MON. 

CARIBBEAN SEA...
AN UPPER RIDGE COVERS THE CARIBBEAN WITH THE AXIS EXTENDING FROM 
COLOMBIA THROUGH THE WINDWARD PASSAGE TO OVER THE W ATLC. 
REMNANT LOW LEVEL MOISTURE REMAINS OVER THE E CARIBBEAN WITH 
ISOLATED SHOWERS WITHIN 75 NM OF A LINE FROM NEAR GUADELOUPE THE 
LEEWARD ISLANDS TO NEAR 13N70W. THE TRADE WINDS ARE INTERACTING 
THE APPROACHING FRONT IN THE GULF OF MEXICO GENERATING SCATTERED 
SHOWERS/ISOLATED THUNDERSTORMS OVER THE W CARIBBEAN S OF 22N W 
OF 80W TO INLAND OVER CENTRAL AMERICA/YUCATAN PENINSULA AND 
WITHIN 60 NM ALONG THE COAST OF PANAMA W OF 80W TO COLOMBIA. 
HIGH PRESSURE OVER THE W ATLC WILL MAINTAIN MODERATE TO FRESH 
TRADE WINDS MAINLY OVER AREA TODAY AND TONIGHT. A COLD FRONT 
WILL MOVE INTO THE NW CARIBBEAN BY LATE SAT BECOMING DIFFUSE 
FROM CENTRAL CUBA TO E HONDURAS BY SUN THEN STALL AND BECOME 
DIFFUSE MON.  

ATLANTIC OCEAN...
AN UPPER RIDGE OVER THE CARIBBEAN COVERS THE W ATLC WITH THE 
AXIS EXTENDING THROUGH THE WINDWARD PASSAGE TO BEYOND 32N67W. A 
WEAK SURFACE RIDGE COVERS THE W ATLC W OF 65W ANCHORED BY A 1018 
MB HIGH NEAR 27N73W. AN UPPER TROUGH REMAINS OVER THE CENTRAL 
ATLC N OF 15N BETWEEN 42W-65W SUPPORTING A COLD FRONT THAT 
ENTERS THE AREA NEAR 32N50W ALONG 27N52W TO 24N56W THEN 
DISSIPATES TO 22N62W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS 
ARE WITHIN 180 NM E OF THE FRONT N OF 28N AND ISOLATED SHOWERS 
WITHIN 75 NM E OF THE REMAINDER OF THE FRONT. REMNANT MOISTURE 
REMAINS E OF THE FRONT GENERATING SCATTERED SHOWERS WITHIN 75 NM 
OF LINE FROM 21N53W TO 31N42W. A SURFACE TROUGH IS IN THE W 
TROPICAL ATLC APPROACHING THE LESSER ANTILLES EXTENDING FROM 
17N57W TO 11N60W GENERATING SCATTERED SHOWERS AND POSSIBLE 
ISOLATED THUNDERSTORMS FROM 11N-17N E OF THE TROUGH TO 51W. A 
BROAD E/W UPPER RIDGE DOMINATES THE TROPICAL ATLC E OF 50W. A 
BROAD SURFACE RIDGE DOMINATES THE E ATLC N OF 15N E OF 49W 
ANCHORED BY A 1029 MB HIGH JUST W OF THE AZORES. THIS IS LEAVING 
THE REMAINDER OF THE ATLC WITH FAIR WEATHER AGAIN THIS MORNING. 
SURFACE RIDGE WILL REMAIN OVER THE W ATLC THROUGH FRI NIGHT. THE 
NEXT COLD FRONT WILL ENTER THE W ATLC ON SUN THEN WILL MOVE 
SLOWLY THROUGH THE W ATLC MON. THE CENTRAL ATLC COLD FRONT WILL 
DISSIPATE TODAY AS THE SURFACE LOW MOVES E THROUGH FRI. THE LOW 
WILL THEN MOVE NE OUT OF THE AREA ON SAT. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
PAW