000 AXNT20 KNHC 071027 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED MAY 07 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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 0945 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 55W S OF 12N MOVING W 15-20 KT. WAVE REMAINS WEAK AND MOVING OVER SOUTH AMERICA WHICH WILL CONTINUE TO WEAKEN IT FURTHER. NO ASSOCIATED SHOWERS OR CONVECTION. ...ITCZ... ITCZ AXIS IS ALONG 5N4W 4N12W 4N22W 1N33W INTO SOUTH AMERICA NEAR 1N51W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM OF THE ITCZ AXIS FROM 3W-8W...WITHIN 60 NM OF LINE FROM 3N24W ACROSS THE EQUATOR NEAR 22W...WITHIN 90 NM OF LINE FROM 3N30W ACROSS THE EQUATOR NEAR 28W AND FROM 3N TO THE EQUATOR W OF 47W TO INLAND OVER SOUTH AMERICA. CLUSTERS OF SIMILAR CONVECTION ARE FROM 7N TO THE EQUATOR BETWEEN 6W-13W AND WITHIN 60 NM OF THE ITCZ AXIS FROM 34W-38W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE COVERS THE GULF WITH THE AXIS EXTENDING FROM THE W BAY OF CAMPECHE TO OVER THE SE US JUST E OF THE MISSISSIPPI VALLEY. MODERATE SUBSIDENCE AND DRY AIR DOMINATES THE AREA RESULTING IN MOSTLY CLEAR SKIES OVER THE GULF THIS MORNING. A WEAK 1016 MB HIGH IS IN THE NE GULF NEAR 28N86W AND IS BEGINNING TO DISSIPATE. MODERATE/STRONG SOUTHERLY SURFACE WINDS ARE OVER THE W GULF DUE TO THE RETURN FLOW AROUND THE SURFACE RIDGE THAT IS ANCHORED OFF THE NORTH CAROLINA COAST. BROAD UPPER TROUGH OVER THE W ATLC EXTENDS TO OVER FLORIDA DIPPING S INTO THE NW CARIBBEAN. CARIBBEAN SEA... BROAD UPPER TROUGH IN THE W ATLC DIPS S OVER THE NW CARIBBEAN N OF 17N FROM THE CENTRAL CUBA TO THE MONA PASSAGE. BROAD UPPER RIDGE COVERS THE THE REMAINDER OF THE CARIBBEAN ANCHORED IN THE W TROPICAL ATLC WITH THE AXIS EXTENDING W ACROSS VENEZUELA AND COLOMBIA TO NICARAGUA. MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR DOMINATES MUSH OF THE CARIBBEAN WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS BEING GENERATED ALONG THE COAST BETWEEN COLOMBIA AND PANAMA TO 10N. MODERATE/STRONG E TRADE WINDS COVER MOST OF THE CARIBBEAN WITH THE STRONGEST WINDS ALONG THE COAST OF COLOMBIA. THESE TRADE WINDS ARE ALSO GENERATING A SMALL AREA OF POSSIBLE ISOLATED SHOWERS FROM 14N-18N BETWEEN 78W-87W. OTHERWISE THE AREA REMAINS RATHER CLEAR THIS MORNING. ATLANTIC OCEAN... BROAD UPPER TROUGH COVERS THE W ATLC BETWEEN 50W AND FLORIDA DIPPING S INTO THE NW CARIBBEAN. AN INTENSE SHORTWAVE IS EMBEDDED WITHIN THIS FLOW EXTENDING ALONG 31N64W TO 25N69W. A COLD FRONT ENTERS THE REGION JUST E OF BERMUDA SW TO 28N73W WHERE IT CONTINUES AS A STATIONARY BOUNDARY TO A 1014 MB LOW JUST N OF GRAND BAHAMA ISLAND NEAR 27N78W WITH A SURFACE TROUGH EXTENDING S JUST OFF THE SE COAST OF FLORIDA TO THE N COAST OF CUBA NEAR HAVANA. A SECOND SURFACE TROUGH ALSO EXTENDS FROM 25N71W TO OVER THE TURKS AND CAICOS NEAR 22N74W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS AS INDICATED BY LIGHTENING DATA ARE TO THE E WITHIN 90 NM OF LINE FROM 26N67W TO BEYOND 32N61W WITH THE HEAVIEST ACTIVITY N OF 28N. SIMILAR ACTIVITY IS WITHIN 45 NM OF 24N FROM 62W-67W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 75 NM ALONG THE N COAST OF CUBA E OF 77W. THE REMAINDER OF THE ATLC IS DOMINATE BY A DEEP LAYERED RIDGE WITH THE UPPER RIDGE ANCHORED OVER THE CAPE VERDE ISLANDS AND THE SURFACE RIDGE ANCHORED BY A 1024 MB HIGH NEAR 33N42W. THE FIRST VISIBLE SATELLITE IMAGES AND SAHARAN AIR LAYER TRACKER FROM CIMSS INDICATES THE THAT AFRICAN DUST COVERS MOST OF THE TROPICAL ATLC S OF 20N E OF 55W. $$ WALLACE