000 AXNT20 KNHC 230540 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE SEP 23 2014 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 0530 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS MOVING ACROSS THE CAPE VERDE ISLANDS WITH AXIS EXTENDING FROM 22N25W TO A 1012 MB LOW NEAR 17N27W TO 12N27W MOVING W AT 10-15 KT. A SLOT OF WARM DRY AIR W OF THE LOW CENTER IS DEPICTED IN THE SSMI TPW AND THE METEOSAT SAL IMAGERY. SAHARAN DUST IS ALSO IN THE WAVE ENVIRONMENT...RESULTING IN THE LACK OF CONVECTION. A TROPICAL WAVE IS ON THE CENTRAL ATLANTIC WITH AXIS EXTENDING FROM 18N43W TO 09N46W...MOVING W AT 20 KT. DRY AND STABLE SAHARAN AIR IS ALSO IN THE ENVIRONMENT OF THIS WAVE...LIMITING THE CONVECTION TO THE SOUTHERN PORTION OF THE WAVE AXIS WHICH CUTS THE MONSOON TROUGH FROM 09N-11N BETWEEN 44W-47W. A TROPICAL WAVE IS MOVING ACROSS THE MONA PASSAGE IN THE CARIBBEAN WITH AXIS EXTENDING FROM 21N67W TO 11N67W...MOVING W AT 10 KT. DEEP LAYER MODERATE MOISTURE ACCOMPANIES THIS WAVE... WHICH ALONG LOW-LEVEL MOISTURE CONVERGENCE AND UPPER-LEVEL DIFFLUENCE HELPS TO GENERATE SCATTERED MODERATE CONVECTION MAINLY ACROSS THE NORTHERN PORTION OF THE WAVE AXIS N OF 17N BETWEEN 64W-69W. A TROPICAL WAVE IS ACROSS WESTERN CUBA WITH AXIS EXTENDING FROM 23N83W TO NORTHERN COSTA RICA NEAR 10N85W. THIS WAVE IS MOVING W AT 10 KT. DRY AIR SUBSIDENCE FROM ALOFT IS LIMITING THE DEVELOPMENT OF CONVECTION ACROSS THE WAVE. SCATTERED MODERATE CONVECTION IS LIMITED TO THE NORTHERN PORTION OF THE WAVE AXIS...WHICH IS BEING ENHANCED BY AN UPPER-LEVEL TROUGH LOCATED ACROSS THE EASTERN GULF AND EXTENDING TO THE YUCATAN PENINSULA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 16N20W TO A 1012 MB LOW NEAR 17N27W TO 12N31W TO 10N45W 08N48W. ASIDE FROM CONVECTION OCCURRING WITH THE TROPICAL WAVES...ISOLATED MODERATE CONVECTION IS ALONG 12N BETWEEN 33W-41W. ...DISCUSSION... GULF OF MEXICO... A UPPER-LEVEL TROUGH ALONG THE EASTERN US EXTENDS ITS BASE ACROSS THE EASTERN GULF AND ACROSS THE FLORIDA PENINSULA. THIS TROUGH SUPPORTS A PAIR OF FRONTAL BOUNDARIES...A STATIONARY FRONT ANALYZED ACROSS NORTHERN FLORIDA CONNECTING TO A 1012 MB LOW NEAR 28N85W TO 26N90W AND A COLD FRONT ACROSS THE SE US EXTENDING ACROSS THE N GULF WATERS TO LOUISIANA. THE COLD FRONT IS FORECAST TO MERGE WITH THE STATIONARY ONE SOMETIME TODAY. SE OF THE UPPER-LEVEL TROUGH...RIDGING IS GENERATING DIFFLUENT FLOW WHICH ALONG THE ABUNDANT LOW-LEVEL MOISTURE ADVECTED FROM THE CARIBBEAN SUPPORTS SCATTERED MODERATE CONVECTION S OF THE STATIONARY FRONT S OF 26N...E OF 90W. OVER THE NEXT 24-48 HOURS...THE FRONT WILL DISSIPATE WHILE MOVING ACROSS CENTRAL FLORIDA. A TROPICAL WAVE IS EXPECTED TO MOVE INTO THE BAY OF CAMPECHE BY THURSDAY. CARIBBEAN SEA... TWO TROPICAL WAVES ARE IMPACTING THE CARIBBEAN...FOR MORE INFORMATION ABOUT THESE REFER TO THE SECTION ABOVE. AN UPPER- LEVEL LOW WITH CENTER NEAR 18N82W IS ENHANCING SCATTERED MODERATE CONVECTION FROM 17N-19N BETWEEN 81W-83W. LOW-LEVEL MOISTURE CONVERGENCE IS ENHANCING SCATTERED MODERATE TO STRONG CONVECTION ACROSS THE WESTERN CARIBBEAN MAINLY W OF CUBA. SCATTERED MODERATE CONVECTION PREVAILS ACROSS CENTRAL AMERICA AND THE SOUTHERN CARIBBEAN WATERS S OF 11N ENHANCED BY THE MONSOON TROUGH AXIS THAT EXTENDS FROM COLOMBIA TO COSTA RICA. OVER THE NEXT 24-48 HOURS...THE TROPICAL WAVE ON THE EASTERN CARIBBEAN IS EXPECTED TO MOVE ACROSS HISPANIOLA AND THE CENTRAL CARIBBEAN ENHANCING CONVECTION. ...HISPANIOLA... SCATTERED SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS THE NE HISPANIOLA AS THE TROPICAL WAVE APPROACHES. AN INCREASE IN CONVECTIVE ACTIVITY IS EXPECTED OVER THE NEXT 24 HOURS AS THE TROPICAL WAVE MOVES ACROSS THE ISLAND AND ADJACENT WATERS. ATLANTIC OCEAN... AN UPPER-LEVEL TROUGH IS OVER THE EASTERN US THAT SUPPORTS A STATIONARY FRONT ANALYZED FROM 30N78W TO 31N81W AND THEN ACROSS NORTHERN FLORIDA INTO THE EASTERN GULF WATERS. AN UPPER-LEVEL HIGH CONTINUES ACROSS THE WESTERN ATLANTIC WITH CENTER NEAR 31N64W NEAR THE END OF A COLD FRONT. THESE SYSTEMS ARE KEEPING A DIFFLUENT FLOW BETWEEN THEM GENERATING MODERATE TO STRONG CONVECTION ACROSS THE BAHAMAS AND THE SOUTH FLORIDA ATLANTIC WATERS FROM 24N-29N BETWEEN 77W-80W. THERE IS ALSO ISOLATED CONVECTION NEAR THE CENTER OF THIS UPPER LEVEL HIGH FROM 33N-36N BETWEEN 60W-66W. TO THE E...AN UPPER-LEVEL LOW CENTERED NEAR 24N55W IS SUPPORTING ISOLATED MODERATE CONVECTION FROM 22N-31N BETWEEN 46W-58W. AT THE SURFACE...THE TAIL END OF A FRONTAL BOUNDARY ANALYZED AS A DISSIPATING COLD FRONT FROM 31N31W TO 27N43W HAS ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THIS FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA