000 AXNT20 KNHC 160959 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED JUL 16 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0930 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 07N30W TO 14N28W MOVING W AT 15 KT. THE WAVE COINCIDES WITH GLOBAL MODEL INDICATED 700 MB TROUGHING AND AN 850 MB RELATIVE VORTICITY MAXIMUM IN THE VICINITY OF 09N30W ALONG THE WAVE AXIS. ISOLATED MODERATE CONVECTION IS FROM 05N-10N BETWEEN 26W-33W. TROPICAL WAVE EXTENDS FROM 09N52W TO 19N49W MOVING W AT 15-20 KT. THE WAVE COINCIDES WITH A BROAD 700 MB TROUGH BETWEEN 46W- 55W. NO SIGNIFICANT DEEP CONVECTION IS NOTED WITH THE WAVE AT THIS TIME. TROPICAL WAVE EXTENDS FROM 10N82W TO 20N79W MOVING W AT 15-20 KT. NORTHWESTERLY FLOW ALOFT DOMINATES THE OVERALL ENVIRONMENT THE WAVE IS MOVING BENEATH PROVIDING RELATIVELY STABLE CONDITIONS. NO SIGNIFICANT DEEP CONVECTION IS NOTED ON SATELLITE IMAGERY. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 16N17W TO 07N30W TO 06N35W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N35W TO 06N56W. A SURFACE TROUGH REMAINS EMBEDDED WITHIN THE ITCZ ANALYZED FROM 07N45W TO 12N43W. ISOLATED MODERATE CONVECTION IS FROM 09N-11N BETWEEN 14W-17W...AND FROM 04N-11N BETWEEN 45W-50W. ...DISCUSSION... GULF OF MEXICO... A LONGWAVE MIDDLE TO UPPER LEVEL TROUGH IS NOTED OVER THE EASTERN HALF OF THE CONUS THAT DIPS ITS BASE SOUTHWARD OVER THE SE CONUS AND GULF COAST E OF 92W. THE TROUGHING SUPPORTS A COLD FRONT ANALYZED FROM CENTRAL GEORGIA THROUGH SOUTHERN LOUISIANA WITH A PRE-FRONTAL SURFACE TROUGH EXTENDING FROM THE FLORIDA PANHANDLE WEST TO GALVESTON BAY. LOW-LEVEL MOISTURE CONVERGENCE SOUTH OF THESE BOUNDARIES ALONG WITH THE MARGINAL MIDDLE TO UPPER LEVEL DYNAMICS GENERATED BY THE UPPER LEVEL TROUGH IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS N OF 26N BETWEEN 82W-93W. FATHER SOUTH...AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER SOUTHERN MEXICO NEAR 17N94W THAT IS PROVIDING AN OVERALL DIFFLUENT ENVIRONMENT S OF 24N. IN BETWEEN HOWEVER...A WEAK SURFACE RIDGE ANCHORED BY A 1017 MB HIGH CENTERED NEAR 24N85W IS MAINTAINING MOSTLY CLEAR SKIES FROM 23N- 26N BETWEEN THE FLORIDA STRAITS AND NE COAST OF MEXICO. ACROSS THE SW GULF...WHILE SURFACE RIDGING PREVAILS...MIDDLE TO UPPER LEVEL MOISTURE AND CLOUDINESS IS NOTED ON SATELLITE IMAGERY S OF 23N BETWEEN THE YUCATAN CHANNEL REGION AND 96W. ISOLATED SHOWERS AND TSTMS ARE OCCURRING IN THE VICINITY OF 20N95W THIS MORNING. LOOKING AHEAD...THE FRONT IS EXPECTED TO SKIRT THE FAR NORTHEASTERN GULF WATERS WHILE BECOMING STATIONARY AND WEAKENING THROUGH LATE THURSDAY. THE SURFACE RIDGE IS FORECAST TO SLIDE EASTWARD WITH SOUTH-SOUTHEASTERLY RETURN FLOW INCREASING FRIDAY INTO THE WEEKEND AS AN AREA OF LOW PRESSURE DEVELOPS ACROSS TEXAS AND MOVES E-NE TO THE MID-MISSISSIPPI RIVER AND OHIO VALLEYS FRIDAY THROUGH THE UPCOMING WEEKEND. CARIBBEAN SEA... NORTHWESTERLY FLOW ALOFT PREVAILS OVER THE WESTERN CARIBBEAN W OF 73W THAT IS PROVIDING OVERALL STABLE CONDITIONS ALOFT THIS MORNING. A FEW ISOLATED SHOWERS ARE OCCURRING N OF 16N W OF 75W...HOWEVER NO SIGNIFICANT DEEP CONVECTION IS PRESENT...EVEN WITH THE PRESENCE OF A TROPICAL WAVE MOVING ACROSS THE WESTERN CARIBBEAN ALONG 80W/81W. FARTHER EAST...AN UPPER LEVEL TROUGH AXIS EXTENDS SOUTHWARD ALONG 70W STEMMING FROM AN UPPER LEVEL LOW CENTERED OVER THE SW NORTH ATLC NEAR 28N71W. THE TROUGHING AND MARGINAL LIFTING DYNAMICS ASSOCIATED WITH IT CONTINUE TO GENERATE SCATTERED CLOUDINESS AND POSSIBLE ISOLATED SHOWERS N OF 17N BETWEEN 60W-75W...INCLUDING HISPANIOLA...PUERTO RICO...AND THE WINDWARD PASSAGE REGION. OTHERWISE...ACROSS THE SE CARIBBEAN...UPPER LEVEL DIFFLUENT FLOW ON THE WESTERN PERIPHERY OF AN UPPER LEVEL RIDGE IS GENERATING ISOLATED SHOWERS AND TSTMS ACROSS THE WINDWARD ISLANDS AND ADJACENT COASTAL WATERS BETWEEN 57W-67W. FINALLY...MODERATE TO FRESH TRADES ARE EXPECTED TO PERSIST THROUGH THE REMAINDER OF THE WEEK AS AREAL COVERAGE GROWS SLIGHTLY NORTHWARD AND WESTWARD LATE WEDNESDAY THROUGH SATURDAY GENERALLY S OF 17N BETWEEN 67W-82W DUE TO STRONG HIGH PRESSURE EXPECTED ACROSS THE CENTRAL ATLC. ...HISPANIOLA... CURRENTLY A FEW ISOLATED SHOWERS ARE NOTED ACROSS THE ISLAND DUE TO A MIDDLE TO UPPER LEVEL TROUGH WITH AXIS EXTENDING ALONG 70W. WITH THE UPPER LEVEL FEATURE SLOW TO MOVE WEDNESDAY...AFTERNOON AND EVENING CONVECTION IS ONCE AGAIN LIKELY FOR THE ISLAND ON WEDNESDAY WITH PEAK HEATING AND INSTABILITY. ATLANTIC OCEAN... AN UPPER LEVEL LOW IS CENTERED NEAR 28N71W THAT EXTENDS AN UPPER LEVEL TROUGH AXIS SOUTHWARD ALONG 70W TO A BASE OVER THE SOUTH- CENTRAL CARIBBEAN SEA. THE TROUGHING CONTINUES TO PULL MOISTURE SOUTHWARD ON ITS WESTERN PERIPHERY AWAY FROM A LONGWAVE TROUGH NOTED OVER THE EASTERN CONUS. ISOLATED SHOWERS AND TSTMS ARE OCCURRING OVER A LARGE PORTION OF THE SW NORTH ATLC FROM 20N-29N BETWEEN 70W-80W. TO THE EAST OF THE UPPER LEVEL LOW...MOISTURE CONVERGENCE AND ADVECTION IS MAXIMIZED IN AN AREA OF SCATTERED SHOWERS AND TSTMS OCCURRING FROM 21N-35N BETWEEN 62W-67W. THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1029 MB HIGH CENTERED NEAR 35N52W. THE ONLY EXCEPTION AND WEAKNESS NOTED IN THE RIDGING IS THE PRESENCE OF A COLD FRONT ALONG 32N BETWEEN 37W-43W. A PRE- FRONTAL SURFACE TROUGH IS ANALYZED FROM THE FRONT NEAR 32N35W SW TO 29N45W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM EITHER SIDE OF THE FRONT AND SURFACE TROUGH. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN