000 AXNT20 KNHC 052357 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT JUL 05 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... TROPICAL WAVE EXTENDS FROM 08N32W TO 17N29W MOVING W AT 20 KT. A STRONG SAHARAN AIR LAYER SIGNAL IS NOTED ON METEOSAT-9 IMAGERY TO THE WEST AND NORTH OF THE WAVE THAT CONTINUES TO RESULT IN AN OVERALL LACK OF ANY SIGNIFICANT CONVECTION IN THE VICINITY OF THE WAVE AXIS AT THIS TIME. ISOLATED MODERATE CONVECTION REMAINS CONFINED TO THE ITCZ REGION. TROPICAL WAVE EXTENDS FROM 12N65W TO 21N65W MOVING W AT 20-25 KT. THE WAVE IS RELATIVELY EASY TO IDENTIFY ON VISIBLE GOES-E SATELLITE IMAGERY AND COINCIDES WITH A RELATIVELY BROAD GLOBAL MODEL 700 MB TROUGH MOVING OVER THE EASTERN CARIBBEAN SEA. CONVECTION REMAINS LIMITED AS THE SAHARAN AIR LAYER IMPACTS OVERALL STABILITY WITH THE WAVE...HOWEVER ISOLATED MODERATE CONVECTION IS FROM 18N-23N BETWEEN 63W-68W. TROPICAL WAVE EXTENDS FROM 12N83W TO 22N84W MOVING W AT 20 KT. THE WAVE IS CURRENTLY MOVING BENEATH THE EASTERN PERIPHERY OF AN UPPER LEVEL ANTICYCLONE CENTERED NEAR 19N89W. DUE TO THE RELATIVELY STABILITY OF THE NORTHERLY UPPER LEVEL FLOW AND DRY CONDITIONS TO THE EAST OF THE WAVE AXIS...ONLY ISOLATED MODERATE CONVECTION IS OCCURRING ACROSS INLAND PORTIONS OF CENTRAL NICARAGUA AND HONDURAS...AND PORTIONS OF WESTERN CUBA AND THE ADJACENT COASTAL WATERS N OF 20N BETWEEN 80W-85W. TROPICAL WAVE EXTENDS ACROSS CENTRAL MEXICO INTO THE EAST PACIFIC REGION...PLEASE SEE THE TROPICAL WEATHER DISCUSSION FOR THE EAST PACIFIC UNDER AWIPS/WMO HEADERS MIATWDAT/AXPZ20 FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 12N16W TO 10N21W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 10N21W TO 08N32W TO 04N42W TO 04N52W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 07N-12N BETWEEN 14W-17W. ISOLATED MODERATE CONVECTION IS FROM 03N-07N BETWEEN 07W-22W... AND FROM 06N-10N BETWEEN 24W-38W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW IS CENTERED OVER EAST-CENTRAL MEXICO NEAR 23N99W THAT IS SUPPORTING A BROAD AREA OF MIDDLE TO UPPER LEVEL DIFFLUENCE ACROSS THE WESTERN GULF THIS EVENING. WHILE NO SURFACE BOUNDARY IS IN PLACE ACROSS THE SW GULF...LOW-LEVEL MOISTURE CONVERGENCE COUPLED WITH THE FAVORABLE UPPER LEVEL DYNAMICS IS GENERATING AN AREA OF SCATTERED SHOWERS AND ISOLATED TSTMS FROM 18N-25N BETWEEN 91W-97W. TO THE NORTHEAST...ANOTHER UPPER LEVEL LOW IS CENTERED OVER MISSISSIPPI AND ALABAMA NEAR 33N88W THAT IS PROVIDING MARGINAL MID-LEVEL LIFT OVER THE NORTHERN GULF COAST WITH ISOLATED SHOWERS NOTED N OF 25N BETWEEN 87W-98W...INCLUDING INLAND PORTIONS OF COASTAL TEXAS S OF 30N E OF 99W. OTHERWISE...AT THE SURFACE...A WEAK RIDGE AXIS EXTENDS FROM THE OHIO RIVER VALLEY SW TO COASTAL LOUISIANA NEAR A 1022 MB HIGH CENTERED NEAR 29N92W THEN TO ANOTHER 1022 MB HIGH CENTERED ACROSS EAST-CENTRAL MEXICO NEAR 23N99W. FINALLY...MID- LEVEL TROUGHING IS NOTED ON WATER VAPOR IMAGERY OVER THE NE GULF AND FLORIDA SUPPORTING A WEAK 1019 MB LOW CENTERED NEAR JACKSONVILLE WITH A STATIONARY BOUNDARY EXTENDING WEST ALONG 30N TO 86W. MOST OF THE CONVECTION HOWEVER IS OCCURRING ACROSS INLAND PORTIONS OF THE FLORIDA PENINSULA AND INTO THE SW NORTH ATLC. LOOKING AHEAD...THE SURFACE RIDGING IS EXPECTED TO BUILD GRADUALLY EASTWARD THROUGH MONDAY. CARIBBEAN SEA... UPPER LEVEL ANTICYCLONIC FLOW PREVAILS OVER THE WESTERN CARIBBEAN W OF 80W...WITH A FAIRLY AMPLIFIED MIDDLE TO UPPER LEVEL TROUGH AND ASSOCIATED LOW CENTERED E OF 80W NEAR 20N72W. THE LOW EXTENDS A TROUGH AXIS SOUTHWARD TO A BASE OVER THE SW CARIBBEAN NEAR 10N77W. RESULTING SOUTH-SOUTHWESTERLY WINDS ALOFT ARE NOTED OVER THE EASTERN CARIBBEAN E OF 74W. AT THE SURFACE... MODERATE TO FRESH TRADE WIND FLOW IS NOTED IN GENERALLY FAIR SKIES THIS EVENING...WITH SLIGHTLY HIGHER WINDS...25 TO 30 KT S OF 14N BETWEEN 73W-78W AS DEPICTED ON EARLIER ASCAT PASSES. THE PRESENCE OF TWO TROPICAL WAVES...ONE ALONG 65W AND THE OTHER ALONG 84W ARE GENERATING A FEW ISOLATED SHOWERS AND TSTMS OVER THE NE CARIBBEAN N OF 15N E OF 70W...AND ACROSS THE NW CARIBBEAN N OF 19N AND W OF 84W. ...HISPANIOLA... CURRENTLY FAIR SKIES ARE NOTED ON SATELLITE IMAGERY...HOWEVER A TROPICAL WAVE TO THE EAST ALONG 65W IS BEGINNING TO IMPACT THE ISLAND WITH INCREASED CLOUDINESS AND POSSIBLE ISOLATED SHOWERS THROUGH THE OVERNIGHT HOURS INTO SUNDAY. AS THE TROPICAL WAVE MOVES ACROSS THE ISLAND SUNDAY...SCATTERED SHOWERS AND ISOLATED TSTMS ARE EXPECTED UNTIL THE WAVE PASSES WEST OF THE ISLAND ON MONDAY. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY OVER NORTHERN FLORIDA AND THE SW NORTH ATLC WATERS NEAR 30N81W. THIS UPPER LEVEL TROUGHING AND MID-LEVEL ENERGY IS PROVIDING AN OVERALL DIFFLUENT ENVIRONMENT IN SUPPORT OF A 1019 MB LOW CENTERED NEAR JACKSONVILLE AND A STATIONARY FRONT EXTENDING NE FROM THE LOW CENTER TO 32N80W THEN EASTWARD ALONG 32N TO 72W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING N OF 25N BETWEEN 75W-83W...AND N OF 29N BETWEEN 70W-75W. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1023 MB HIGH CENTERED SE OF BERMUDA NEAR 30N63W. ON THE SOUTHERN PERIPHERY OF THIS HIGH...THE TROPICAL WAVE ALONG 65W CONTINUE TO MOVE WESTWARD WITH ISOLATED SHOWERS AND TSTMS FROM 18N-23N BETWEEN 60W-70W. FARTHER EAST... THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1031 MB HIGH CENTERED W-NW OF THE AZORES NEAR 41N41W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN