000 AXNT20 KNHC 130000 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE AUG 12 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... A TROPICAL WAVE W OF AFRICA EXTENDS FROM 19N21W TO 9N22W. DEEP LAYER MOISTURE ASSOCIATED WITH THIS WAVE IS FROM UPPER-LEVEL DIFFLUENCE ALONG THE MONSOON TROUGH SUPPORTS SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS FROM 9N-15N BETWEEN 17W-25W. A TROPICAL WAVE IN THE CENTRAL ATLC EXTENDS FROM 19N37W THROUGH A 1012 MB LOW NEAR 14N37W TO 10N38W...MOVING W AT 20 KT. SSMI TPW AND METEOSAT SAL TRACKING IMAGERY INDICATE SAHARA DRY AIR IS ENTRAINING INTO THE WAVE ENVIRONMENT AND SUPPRESSING DEVELOPMENT OF DEEP CONVECTION IN NORTHERN AND CENTRAL PORTIONS. SCATTERED MODERATE CONVECTION IS OCCURRING S OF THE LOW CENTER FROM 8N-11N BETWEEN 36W-41W BEING ENHANCED BY UPPER LEVEL DIFFLUENCE. A TROPICAL WAVE IN THE CENTRAL CARIBBEAN EXTENDS FROM 19N75W TO 11N76W MOVING W AT 15-20 KT. THE WAVE HAS MODERATE MOISTURE AT LOW LEVELS...HOWEVER DRY AIR SUBSIDENCE ALOFT IS HINDERING THE DEVELOPMENT OF DEEP CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE WEST AFRICAN COAST NEAR 12N16W TO 12N22W TO 15N32W TO 1012 MB LOW NEAR 14N37W TO 8N46W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM NEAR 8N47W TO 8N51W. IN ADDITION TO SHOWERS ASSOCIATED WITH TROPICAL WAVES SCATTERED MODERATE CONVECTION IS FROM 8N-11N BETWEEN 50W-57W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE-LEVEL TROUGH IS ACROSS THE EASTERN CONUS WITH BASE EXTENDING INTO THE NE COAST OF TEXAS. A WEAK SURFACE TROUGH EXTENDS FROM NORTHERN FLORIDA TO 27N91W AND ENHANCING SCATTERED SHOWERS N OF 26N E OF 93W. AN UPPER LOW CENTERED NEAR 21N90W IS ENHANCING SHOWERS AND TSTMS OVER THE YUCATAN PENINSULA. WEAK SURFACE RIDGING ELSEWHERE ACROSS THE BASIN WITH VARIABLE WINDS OF 5-10 KT. A WEAK COLD FRONT IS EXPECTED TO ENTER THE NORTHERN GULF WED MORNING THEN DISSIPATE THROUGH THU MORNING. CARIBBEAN SEA... THE TROPICAL WAVE IN THE CENTRAL CARIBBEAN IS SUPPORTED BY AN INVERTED TROUGH ALOFT. MODERATE DEEP LAYER MOISTURE ACROSS THE REMAINDER OF THE BASIN SUPPORTING ISOLATED SHOWERS AND FEW TSTMS ON THE NW CARIBBEAN N OF 18N W OF 82W. MODERATE TRADES IN THE CENTRAL AND EASTERN BASIN ARE ASSOCIATED WITH PRESSURE GRADIENT E OF THE TROPICAL WAVE. THE TROPICAL WAVE IS FORECAST TO MOVE INTO CENTRAL AMERICA BY THU MORNING. HISPANIOLA... MODERATELY MOIST DEEP LAYER AIR ACROSS THE ISLAND IS ALLOWING SHOWERS AND TSTMS TO DEVELOP FROM AFTERNOON HEATING. SHOWERS ARE EXPECTED TO DIMINISH TONIGHT THEN FIRE OFF AGAIN WED AFTERNOON. ATLANTIC OCEAN... A BROAD UPPER LEVEL ANTICYCLONE CENTERED NEAR 28N75W PROVIDING FAVORABLE ENVIRONMENT FOR MODERATE SHOWERS AND FEW TSTMS TO DEVELOP N OF 29N BETWEEN 68W AND 80W. A CUT OFF UPPER LOW IS CENTERED NE OF THE VIRGIN ISLANDS NEAR 24N58W. MAJORITY OF THE CENTRAL AND EASTERN ATLC IS INFLUENCED BY SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED SW OF THE AZORES NEAR 36N30W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MUNDELL