000 AXNT20 KNHC 151024 TWDAT TROPICAL WEATHER DISCUSSION... NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE APR 15 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. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N8W 2N20W 1N30W CROSSING THE EQUATOR NEAR 43W AND INTO NE BRAZIL NEAR 1S47W. CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION ARE WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN THE WEST COAST OF AFRICA AND 14W. SIMILAR CLUSTERS OF MODERATE TO STRONG CONVECTION ARE FROM THE EQUATOR TO 6N BETWEEN 20W-25W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 160 NM N OF THE AXIS BETWEEN 36W-45W. ...DISCUSSION... THE GULF OF MEXICO... AS OF 09Z...THE ONLY REMAINING PORTION OF THE COLD FRONT THAT HAS BEEN TRAVERSING THE GULF IS IN THE BAY OF CAMPECHE FROM 19N91W ALONG 19N94W TO 22N97W. THE FRONT IS FAIRLY DRY IN THE GULF WITH ONLY A NARROW BAND OF LOW-LEVEL CLOUDS DEVELOPING ALONG THE BOUNDARY. COLD AIR STRATOCUMULUS CLOUDS CONTINUE TO COVER THE GULF. SHIP AND BUOY OBSERVATIONS INDICATED THAT WINDS IN THE NW GULF HAVE SHIFTED E TO SE AT 5-10 KT. NORTHERLY WINDS COVER THE REMAINDER OF THE GULF...HOWEVER...THESE TOO ARE EXPECTED TO VEER SE AND DIMINISH AS HIGH PRESSURE MOVES INTO THE AREA AND SETS UP RETURN FLOW AROUND THE RIDGE LATER TODAY. ALOFT...NEAR ZONAL FLOW AT THE BASE OF AN UPPER TROUGH RESULTS IN STRONG SUBSIDENCE OVER THE NORTHERN GULF WATERS. THE CARIBBEAN SEA... A FRONTAL BOUNDARY REMAINS ANCHORED IN THE WESTERN CARIBBEAN. AS OF 09Z...THE STATIONARY BOUNDARY STRETCHED FROM SE CUBA NEAR 20N77W TO HONDURAS NEAR 16N86W. TO THE NW...A COLD FRONT HAS ENTERED THE CARIBBEAN AND...AS OF 09Z...WAS ANALYZED FROM SW CUBA NEAR 22N81W TO THE YUCATAN PENINSULA NEAR 20N87W. NE WINDS 10-15 KT AHEAD OF THE BOUNDARY WILL SHIFT NW AND INCREASE TO 20 KT FOLLOWING THE FRONTAL PASSAGE. LOW CLOUDS AND EMBEDDED ISOLATED SHOWERS ARE BETWEEN THE TWO BOUNDARIES. FARTHER EAST...A SFC TROUGH STRETCHING FROM HISPANIOLA TO COLOMBIA CONTINUES TO MOVE WESTWARD THROUGH THE CARIBBEAN. SCATTERED SHOWERS ARE WITHIN 120 NM W OF THE AXIS. BROKEN LOW CLOUDS AND ISOLATED SHOWERS COVER THE CARIBBEAN E OF THE TROUGH. EXPECT THIS TROUGH TO GRADUALLY DISSIPATE AS IT INTERACTS WITH THE FRONTAL BOUNDARIES IN THE WESTERN CARIBBEAN. ALOFT...A FLATTENED UPPER RIDGE RESIDES OVER THE CENTRAL AND WESTERN CARIBBEAN... KEEPING THE ATMOSPHERE FAIRLY STABLE. WESTERN ATLANTIC... THE WEATHER PATTERN IN THE W ATLC IS DEFINED BY THE EXISTENCE OF TWO COLD FRONTS. AS OF 09Z...THE EASTERN-MOST FRONTAL BOUNDARY ENTERS THE REGION NEAR 31N66W AND CONTINUES SW OVER THE BAHAMAS BEFORE CROSSING OVER CUBA NEAR 21N76W. MULTILAYERED CLOUDS WITH EMBEDDED SHOWERS ARE WITHIN 80 NM BEHIND THE BOUNDARY. THE SECOND FRONT ENTERS THE W ATLC NEAR 31N71W AND CONTINUES OVER THE NW BAHAMAS BEFORE CROSSING OVER CUBA NEAR 23N80W. ASSOCIATED CONVECTION IS MOSTLY CONFINED TO THE AREA N OF 25N...WITH LIGHTING DATA INDICATING NUMEROUS ISOLATED THUNDERSTORMS JUST N OF THE DISCUSSION AREA. THE TWO FRONTS ARE EXPECTED TO MERGE AND FORM A SFC LOW NEAR 30N78W LATE TODAY. STRONG N WINDS BEHIND THE FRONT ARE EXPECTED TO REACH GALE FORCE TO THE WEST OF THE DEVELOPING SFC LOW. CENTRAL AND EASTERN ATLANTIC... THE CENTRAL AND EASTERN ATLC REMAIN TRANQUIL UNDER THE INFLUENCE OF A BROAD DEEP-LAYERED RIDGE ANCHORED BY A 1027 MB SFC HIGH NEAR 30N43W. ANTICYCLONIC FLOW AROUND THE RIDGE CONTINUES TO TRANSPORT PATCHY CLOUDS ACROSS THE REGION. IN THE DEEP TROPICS....AN UPPER HIGH IS SITUATED NEAR 9N33W ENHANCING CONVECTION IN THE ITCZ. WLY FLOW N OF THE UPPER RIDGE AND S OF AN ELONGATED UPPER TROUGH IS TRANSPORTING UPPER LEVEL MOISTURE/HIGH CLOUDS FROM S AMERICA TO AFRICA BETWEEN 11N-18N. $$ WADDINGTON