000 AXNT20 KNHC 292336 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN APR 29 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 6N10W 3N25W 3N35W 2N51W. ISOLATED MODERATE TO STRONG CONVECTION IS WITHIN 40-60 NM EITHER SIDE OF THE AXIS E OF 25W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 40 NM N OF THE AXIS BETWEEN 32W-40W. SIMILAR CONVECTION IS OVER NE BRAZIL AND LIBERIA IN AFRICA. ...DISCUSSION... GULF OF MEXICO... WEATHER CONDITIONS ACROSS THE GULF AND THE SE US...INCLUDING THE STATE OF FLORIDA REMAIN FAIRLY QUIET THIS EVENING THANKS TO A SFC RIDGING DOMINATING. AS OF 29/2100 UTC...A 1021 MB HIGH WAS LOCATED OFF THE LOUISIANA COAST NEAR 29N92W. CLEAR SKIES...LIGHT N TO NE WINDS...AND SMALL WAVES ARE NOTED OVER THE GULF WATERS E OF 90W. SCATTERED CLOUD COVER IS OVER MUCH OF THE WRN GULF WITH A BIT MORE MOISTURE AVAILABLE AROUND THE S AND SW PORTION OF THE SFC RIDGE. ALOFT...A MID/UPPER RIDGE DOMINATES THE REGION WITH THE AXIS ALONG 94W...PARTICULARLY IN THE MID LEVELS. SLY WINDS ARE FORECAST TO INCREASE OVER THE WESTERN GULF MON EVENING AS SFC HIGH PRES SLOWLY DRIFTS E ACROSS THE NRN GULF WATERS. THIS FEATURE WILL KEEP CONDITIONS FAIRLY TAME THROUGH EARLY WEEK. THE SLY WIND FLOW WILL CONTINUE TO ADVECT LOW LEVEL MOISTURE OVER THE WESTERN GULF INTO TEXAS OVER THE NEXT COUPLE OF DAYS. CARIBBEAN SEA... THE WEAK SURFACE TROUGH THAT MOVED THROUGH SOUTH FLORIDA ON SATURDAY IS CURRENTLY OVER THE CENTRAL BAHAMAS/E CUBA WHERE IS ENHANCING SCATTERED SHOWERS AND ISOLATED TSTMS...BUT MAINLY OVER E CUBA. THIS TROUGH WILL MOVE ACROSS THE SOUTHERN BAHAMAS AND THE WINDWARD PASSAGE/HAITI TOMORROW MORNING...THEN WILL GRADUALLY DISSIPATE LATE MONDAY. A DIFLUENT PATTERN ALOFT BETWEEN AN UPPER TROUGH OFF THE EAST COAST AND A RIDGE THAT DOMINATES THE ENTIRE BASIN IS SUPPORTING THIS CONVECTIVE ACTIVITY. MODERATE TO FRESH TRADE WINDS CONTINUE TO ADVECT TYPICAL PATCHES OF LOW LEVEL MOISTURE WWD ACROSS THE CARIBBEAN SEA. ONE OF THEM IS CROSSING WITHIN 90 NM SOUTH OF JAMAICA... WHERE SOME LOW LEVEL CONFLUENCE IS NOTED. SIMILAR FRAGMENTS OF LOW LEVEL MOISTURE WITH EMBEDDED SHOWERS ARE MOVING FROM THE TROPICAL NORTH ATLC INTO THE E CARIBBEAN...SOME OF WHICH ARE ALSO AFFECTING PUERTO RICO AND THE VIRGIN ISLANDS. SCATTERED MODERATE CONVECTION IS SEEN OVER N COLOMBIA AND PANAMA DUE TO THE CLOSE PROXIMITY OF THE EPAC ITCZ AND UPPER DIFFLUENCE. MODERATE TO FRESH TRADE WINDS EXPECTED OVER THE CARIB THE NEXT FEW DAYS AS HIGH PRES BUILDS N OF THE AREA. ATLANTIC... WEAK SFC HIGH PRES IS BUILDING INTO THE THE WRN ATLC BEHIND THE SFC TROUGH THAT EXTENDS FROM 29N71W TO OVER THE CENTRAL BAHAMAS/E CUBA. SCATTERED SHOWERS WITH A FEW ISOLATED TSTMS ARE WITHIN 180 NM AHEAD OF THE TROUGH. VERY DRY/STABLE AIR IS BEING ADVECTED INTO THE WRN ATLC IN THE WAKE OF THE DEEP LAYERED TROUGH LOCATED OFF THE EASTERN SEABOARD. WV IMAGERY SHOWS THE BASE OF THIS TROUGH REACHING THE CENTRAL BAHAMAS. A JET STREAM BRANCH WITH CORE WINDS OF 70 TO 90 KT EXTENDS FROM THE BASE OF THIS TROUGH NEWD BEYOND 32N65W. THE REMAINDER OF THE ATLC DISCUSSION AREA IS DOMINATED BY THE SRN PERIPHERY OF A 1028 MB SFC HIGH LOCATED NEAR THE AZORES. THIS HIGH IS PRODUCING A SWATH OF 20 TO 25 KT NE-E WINDS ACROSS THE ATLC MAINLY E OF 53W. THESE WINDS ARE CARRIED POCKETS OF LOW LEVEL MOISTURE ACROSS THE OCEAN INTO THE LESSER ANTILLES AND E CARIBBEAN. WEAK HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE WRN ATLC WHILE MUCH STRONGER AND LARGER HIGH PRESSURE REMAINS IN CONTROL OF THE E-CENTRAL ATLC. OF NOTE...VIS SATELLITE IMAGERY HAS SHOWN A PLUME OF SMOKE AFFECTING NE FLORIDA AND ADJACENT ATLC WATERS...DOWNSTREAM FROM THE LARGE WILDFIRES IN SE GEORGIA. $$ GR