000 AXNT20 KNHC 120548 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU APR 12 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 0345 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 7N10W 2N22W 2N42W CROSSING THE EQUATOR INTO SOUTH AMERICA NEAR 50W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 120/150 NM OF THE AXIS W OF 45W TO INLAND OVER SOUTH AMERICA. SCATTERED CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE WITHIN 180 NM OF THE AXIS W OF 13W ACROSS THE REMAINDER OF THE ATLC. ...DISCUSSION... GULF OF MEXICO... BROAD DEEP LAYERED TROUGH COVERS THE E US AND THE GULF OF MEXICO MOVING INTO THE W ATLC WITH THE UPPER LOW MOVING ACROSS THE UPPER MISSISSIPPI VALLEY. COMPLEX OCCLUDED FRONTAL SYSTEM IS WELL INLAND OVER E US WITH A COLD FRONT ENTERING THE REGION ACROSS CENTRAL ALABAMA...S MISSISSIPPI...AND SE LOUISIANA INTO THE GULF NEAR 29N91W EXTENDING SW INLAND OVER S TEXAS NEAR BROWNSVILLE. A PRE-FRONTAL TROUGH EXTENDS FROM THE FLORIDA PANHANDLE NEAR PANAMA CITY TO NEAR 25N90W. SCATTERED SHOWERS/ WITH SEVERE THUNDERSTORMS ARE E OF THE TROUGH EXTENDING FROM 24N86W TO OVER THE FLORIDA PENINSULA NEAR TAMPA TO DAYTONA BEACH. THESE THUNDERSTORMS HAVE PRODUCED DAMAGING WINDS AND HAIL EARLIER IN EVENING. DRY AIR IS IN WAKE OF THE SURFACE TROUGH LEAVING THE REMAINDER OF THE GULF UNDER CLEAR SKIES TONIGHT. THIS FRONTAL SYSTEM IS EXPECTED TO CROSS THE GULF TODAY AND BEGIN TO WEAKEN BEFORE REACHING THE W ATLC ON FRI WITH THE NEXT FRONTAL PASSAGE ON SAT. CARIBBEAN SEA... BROAD UPPER LEVEL RIDGE COVERS THE CARIBBEAN ANCHORED BY AN UPPER HIGH CENTERED OVER THE SW CARIBBEAN NEAR 12N77W WITH DIFFLUENCE ON THE W SIDE OF THIS UPPER RIDGE ENHANCING SCATTERED SHOWERS/THUNDERSTORMS OVER COSTA RICA AND SE NICARAGUA. SHOWERS AND STRONG THUNDERSTORMS ARE INLAND OVER THE N YUCATAN PENINSULA MOVING E INTO THE NW CARIBBEAN AND THE YUCATAN CHANNEL. DRY AIR AND CLEAR SKIES DOMINATE THE REMAINDER OF THE CARIBBEAN WITH MODERATE/STRONG EASTERLY TRADE WINDS. ATLANTIC OCEAN... A DEEP LAYERED TROUGH OVER THE N/CENTRAL ATLC N OF THE REGION IS DRAPING A COLD FRONT INTO THE AREA ALONG 32N47W TO 30N57W WHERE IT PULLS UP STATIONARY TO A 1009 MB LOW EMBEDDED WITHIN THE BROAD DEEP LAYERED MOVING INTO THE W ATLC FROM THE E US AND GULF OF MEXICO. THE 1009 MB LOW IS CENTERED NEAR 31N75W WITH A FRONTAL BOUNDARY EXTENDING W INTO GEORGIA AND IS ATTACHED TO THE OCCLUDED FRONT OVER THE E US. THIS COMPLEX SYSTEM IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS MOVING OFF THE FLORIDA PENINSULA THAT MOVED ACROSS FLORIDA EARLIER THIS EVENING FROM 27N-30N W OF 79W. BROAD UPPER RIDGE FROM THE CARIBBEAN EXTENDS ACROSS THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC WITH DIFFLUENCE TO THE W GENERATING HEAVY SHOWERS/SCATTERED THUNDERSTORMS WITHIN 125 NM OF LINE FROM 25N75W ACROSS THE BAHAMAS TO CUBA NEAR 22N78W. THESE STORMS PRODUCED OVER 3 INCHES OF RAIN IN NASSAU EARLIER ON WED. BROAD UPPER LOW IS OFF THE COAST OF MOROCCO AFRICA EXTENDS S TO OVER THE CANARY ISLANDS E OF 20W. A SURFACE RIDGE COVERS THE ATLC E OF THE CENTRAL ATLC COLD FRONT ANCHORED BY A 1026 MB HIGH NEAR 32N26W AND EXTENDING S INTO THE TROPICS. THIS IS GIVING THE ATLC E OF 60W FAIR WEATHER CLOUDS AND LITTLE CHANCE OF SHOWERS. $$ WALLACE