000
AXNT20 KNHC 190550
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC NEAR 10N14W ALONG 6N14W TO 3N17W WHERE THE ITCZ AXIS 
CONTINUES ALONG 00N24W 2N39W THEN S OF THE EQUATOR NEAR 47W. 
CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 6N TO 
JUST S OF THE EQUATOR E OF 28W ACROSS THE PRIME MERIDIAN. 
CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 4N TO JUST S 
OF THE EQUATOR BETWEEN 28W-34W. 

...DISCUSSION...

GULF OF MEXICO...
THE UPPER TROUGH OVER THE E CONUS DIPS S INTO THE N GULF 
SUPPORTING A WEAK COLD FRONT AT 19/0300 UTC EXTENDS INTO THE 
GULF FROM A 1013 MB LOW NEAR TALLAHASSEE FLORIDA ALONG 24N86W TO 
OVER THE YUCATAN PENINSULA AND NW GUATEMALA. CLUSTERS OF 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 180 NM E OF 
THE FRONT S OF 26N WITH ISOLATED SHOWERS POSSIBLE E OF THE 
REMAINDER 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 NE ARKANSAS GIVING THE AREA W OF THE FRONT 
MOSTLY CLEAR SKIES TONIGHT. THE COLD FRONT WILL SLOWLY DRIFT 
THROUGH THE E GULF THROUGH THU. A STRONGER COLD FRONT WILL ENTER 
THE W GULF FRI NIGHT AND REACH FROM SE LOUISIANA TO THE BAY OF 
CAMPECHE EARLY SAT WITH A LOW ALONG THE FRONT. THE LOW WILL BE 
IN THE N/CENTRAL GULF ON SUN WITH THE FRONT EXTENDING TO THE BAY 
OF CAMPECHE EXITING THE AREA OF MON. 

CARIBBEAN SEA...
AN UPPER RIDGE COVERS THE CARIBBEAN WITH THE AXIS EXTENDING 
FROM COLOMBIA ACROSS CUBA INTO THE W ATLC. REMNANT LOW LEVEL 
MOISTURE REMAINS OVER THE E CARIBBEAN WITH ISOLATED SHOWERS 
WITHIN 90/120 NM OF A LINE FROM 14N68W ACROSS THE LEEWARD 
ISLANDS NEAR DOMINICA INTO THE W TROPICAL ATLC. 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 AND 
THE YUCATAN PENINSULA. THE FRONT CURRENTLY IN THE GULF OF MEXICO 
WILL BECOME DIFFUSE BEFORE ENTERING THE CARIBBEAN. HIGH 
PRESSURE NE OF THE BAHAMAS WILL MAINTAIN MODERATE TO FRESH TRADE 
WINDS MAINLY OVER THE E AND CENTRAL CARIBBEAN THROUGH FRI. A 
COLD FRONT WILL MOVE INTO THE NW CARIBBEAN BY LATE SAT BECOMING 
DIFFUSE FROM CENTRAL CUBA TO E HONDURAS BY LATE SUN.  

ATLANTIC OCEAN...
AN UPPER RIDGE OVER THE CARIBBEAN COVERS THE W ATLC WITH THE 
AXIS EXTENDING ACROSS CUBA NEAR 21N77W TO BEYOND 32N70W COVERING 
THE W ATLC W OF 65W WITH A WEAK SURFACE RIDGE COVERING THE SAME 
AREA ANCHORED BY A 1020 MB HIGH NEAR 29N75W. AN UPPER TROUGH 
REMAINS OVER THE CENTRAL ATLC N OF 15N BETWEEN 42W-75W 
SUPPORTING A COLD FRONT THAT ENTERS THE AREA NEAR 32N52W ALONG 
28N52W TO 24N56W THEN DISSIPATES TO 23N63W. SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS ARE WITHIN 180 NM E OF THE FRONT N OF 
26N. A SURFACE TROUGH IS TO THE SE EXTENDING FROM 31N46W 23N49W 
18N60W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 120 
NM EITHER SIDE OF THE TROUGH N OF 26N WITH ISOLATED SHOWERS 
WITHIN 60 NM EITHER SIDE OF THE REMAINDER OF THE TROUGH. A 
SURFACE TROUGH IS IN THE W TROPICAL ATLC JUST W OF THE LESSER 
ANTILLES EXTENDING FROM 17N57W TO 10N59W GENERATING SCATTERED 
SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 11N-17N E OF 
THE TROUGH TO 48W. 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 44W ANCHORED BY A 1031 MB HIGH JUST W OF THE 
AZORES. THIS IS LEAVING THE REMAINDER OF THE ATLC WITH FAIR 
WEATHER TONIGHT. SURFACE RIDGE WILL REMAIN OVER THE W ATLC 
THROUGH SAT THE SHIFTING NE AHEAD OF THE NEXT COLD FRONT TO 
ENTER THE W ATLC ON SUN. THE FRONT WILL MOVE SLOWLY THROUGH THE 
W ATLC MON. THE CENTRAL ATLC COLD FRONT WILL DISSIPATE THU AS 
THE SURFACE LOW MOVES E THROUGH FRI. THE LOW WILL THEN MOVE NE 
OUT OF THE AREA SAT. 

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

$$
PAW