000 AXNT20 KNHC 010537 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON SEP 1 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. ...SPECIAL FEATURE... A TROPICAL WAVE IS OVER THE YUCATAN PENINSULA AND THE BAY OF CAMPECHE WITH AXIS EXTENDING FROM 23N90W TO 15N91W...MOVING W AT 5 KT. LOW LEVEL CYCLONIC TURNING IS NOTED ON VISIBLE SATELLITE IMAGERY AND CURRENT OBSERVATIONS OVER THE WESTERN HALF OF THE YUCATAN PENINSULA. SCATTERED MODERATE CONVECTION CONTINUES IN THE PROXIMITY OF THE WAVE AXIS ACROSS THE YUCATAN PENINSULA AND EXTENDING TO SOUTHERN MEXICO. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE CONDUCIVE FOR TROPICAL CYCLOGENESIS AS THE SYSTEM CONTINUES TO MOVE ACROSS THE SOUTHWESTERN GULF OF MEXICO. A MEDIUM CHANCE FOR TROPICAL CYCLONE DEVELOPMENT IS EXPECTED DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... A TROPICAL WAVE IS ON THE EASTERN ATLC WITH AXIS JUST EAST OF THE CAPE VERDE ISLANDS ALONG 17N23W TO 07N24W...MOVING W AT 10- 15 KT. THE WAVE EXHIBIT A STRONG SIGNAL IN THE MIDDLE AND UPPER LEVELS AND ITS SOUTHERN END IS EMBEDDED IN THE MONSOON TROUGH. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE FROM 8N-12N BETWEEN 23W-26W. ISOLATED SHOWERS CONTINUE W OF THE AXIS ALONG 20W...BETWEEN 12N-15N. A TROPICAL WAVE IS ON THE CENTRAL ATLC WITH AXIS EXTENDING FROM 16N38W TO 09N41W...MOVING WEST AT 15-20 KT. SAHARAN DRY AIR AND DUST IS IN THE ENVIRONMENT OF THE WAVE...WHICH IS LIMITING CONVECTION TO ISOLATED SHOWERS AND TSTMS FROM 10N-12N...BETWEEN 42W-45W. A TROPICAL WAVE IS WITHIN 400 NM EAST OF THE LESSER ANTILLES WITH AXIS EXTENDING FROM 19N54W TO 08N54W...MOVING WEST AT 10-15 KT. SAHARAN DRY AIR AND DUST IS IN THE ENVIRONMENT OF THE WAVE...WHICH IS LIMITING CONVECTION TO ISOLATED SHOWERS AND TSTMS ALONG 10N...BETWEEN 54W-56W. A TROPICAL WAVE IS WITHIN 20 NM EAST OF FAJARDO...PUERTO RICO... WITH AXIS EXTENDING FROM 19N65W TO 09N65W MOVING WEST AT 10 KT. THE WAVE IS ASSOCIATED WITH MODERATE LOW-LEVEL MOISTURE AS DEPICTED ON TPW IMAGERY. STRONG DEEP LAYER ENVIRONMENTAL SHEAR IS INHIBITING DEEP CONVECTION. DESPITE THIS...ISOLATED SHOWERS ARE POSSIBLE IN THE PROXIMITY OF THIS WAVE. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 11N16W AND CONTINUES ALONG 07N24W TO 09N40W TO 08N45W. THE ITCZ EXTENDS FROM 08N45W TO THE COAST OF GUYANA AT 07N59W. FOR INFORMATION ABOUT CONVECTION...PLEASE SEE THE TROPICAL WAVES SECTION. ...DISCUSSION... GULF OF MEXICO... THE MAIN FEATURE IN THE GULF IS A TROPICAL WAVE MOVING ACROSS THE YUCATAN PENINSULA AND EASTERN BAY OF CAMPECHE WITH A MEDIUM POTENTIAL OF BECOMING A TROPICAL CYCLONE WITHIN THE NEXT 48 HOURS. A MID-TO-LOW LEVEL CYCLONIC CIRCULATION AND AN UPPER LEVEL INVERTED TROUGH ARE SUPPORTING THIS WAVE. MODERATE DEEP LAYER MOISTURE IS ALSO PRESENT IN THE ENVIRONMENT OF THIS WAVE...WHICH IS FUELING SCATTERED SHOWERS AND TSTMS ACROSS THE YUCATAN PENINSULA AND ISOLATED ACTIVITY ACROSS THE SOUTHERN GULF WATERS MAINLY S OF 22N. FOR MORE INFORMATION ABOUT THIS WAVE...SEE THE SPECIAL FEATURES SECTION ABOVE. AN UPPER LEVEL RIDGE CONTINUES ACROSS THE NW GULF...WITH CENTER NEAR 26N94W. WITH THIS...UPPER LEVEL DIFFLUENCE WILL CONTINUE ACROSS THE SOUTHERN GULF WATERS OVER THE NEXT 24 HOURS WHICH WILL ENHANCE THE CHANCE OF SHOWERS AND TSTMS AS THE WAVE DISCUSSED ABOVE CONTINUES MOVING W. WEAK SURFACE RIDGING WILL PREVAIL ELSEWHERE WITHIN THAT PERIOD. SE FLOW AT 10-15 KT PREVAILS ACROSS THE BASIN. CARIBBEAN SEA... AN AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE OVER THE SW GULF OF MEXICO CONTINUES TO ENHANCE THE SHOWERS AND TSTMS DEVELOPING ACROSS THE W CARIBBEAN MAINLY W OF 85W. SEE THE SPECIAL FEATURE SECTION ABOVE FOR MORE INFORMATION. THE TROPICAL WAVE ALONG 54W DISCUSSED ABOVE IS LOCATED IN AN AREA OF STRONG DEEP LAYER ENVIRONMENTAL WIND SHEAR WHICH IS HINDERING THE DEVELOPMENT OF CONVECTION IN THE VICINITY OF THIS FEATURE. AN UPPER LEVEL ELONGATED LOW ANCHORED NEAR THE SOUTHERN BAHAMAS AT 23N73W ALONG WITH MODERATE LOW LEVEL MOISTURE IS SUPPORTING THE DEVELOPMENT OF ISOLATED SHOWERS ACROSS WESTERN HISPANIOLA. FAIR WEATHER DOMINATES ELSEWHERE. TRADES OF 10-15 KT DOMINATE THE BASIN...EXCEPT FOR THE FAR NW CARIBBEAN W OF 84W AND THE CENTRAL BASIN S OF 15W BETWEEN 67W-80W WHERE 15-20 KT WINDS PERSIST. THE TROPICAL WAVE E OF PUERTO RICO WILL CONTINUE MOVING ACROSS THE CARIBBEAN TUESDAY ENHANCING MORE SHOWERS FOR HISPANIOLA. A NEW TROPICAL WAVE ENTERS THE BASIN BY TUESDAY MORNING. ...HISPANIOLA... AN ELONGATED UPPER LEVEL LOW ANCHORED NEAR THE SOUTHERN BAHAMAS ALONG WITH MODERATE LOW LEVEL MOISTURE IS SUPPORTING ISOLATED CONVECTION ACROSS WESTERN HALF OF THE ISLAND. A TROPICAL WAVE CURRENTLY E OF PUERTO RICO WILL MOVE ACROSS THE ISLAND THROUGH TUE ENHANCING MORE SHOWERS FOR HISPANIOLA. ATLANTIC OCEAN... AN ELONGATED UPPER LEVEL LOW ANCHORED NEAR THE SOUTHERN BAHAMAS REFLECTS AT THE SURFACE AS TWO SURFACE TROUGHS...ONE ALONG 26N68W TO 20N72W AND A SECOND ONE FROM 32N68W TO 28N70W. ISOLATED MODERATE CONVECTION IS ASSOCIATED WITH THESE FEATURES ARE S OF 29N BETWEEN 64W-75W. FARTHER EAST...A TROUGH ALOFT SUPPORT A DISSIPATING COLD FRONT ANALYZED FROM 27N50W TO A 1012 MB LOW NEAR 40N37W. ISOLATED CONVECTION IS MOVING S ALONG THIS BOUNDARY. SURFACE RIDGING AND FAIR WEATHER CONTINUES ACROSS THE REST OF THE BASIN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA