000 AXNT20 KNHC 121045 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN JUL 12 2015 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 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 10N30W TO 20N28W MOVING W AT 10-15 KT. THE WAVE COINCIDES WITH A 700 MB TROUGH BETWEEN 26W-36W AND A MAXIMUM IN 850 MB RELATIVE VORTICITY ALONG THE WAVE AXIS NEAR 14N. NO SIGNIFICANT CONVECTION IS NOTED ON SATELLITE IMAGERY DUE TO SAHARAN DUST THAT COVERS A LARGE PORTION OF THE TROPICAL NORTH ATLC. TROPICAL WAVE EXTENDS FROM 09N50W TO 19N47W MOVING W AT 15 KT. THE WAVE COINCIDES WITH A RELATIVELY BROAD 700 MB GLOBAL MODEL INDICATED TROUGH BETWEEN 45W-55W. NO SIGNIFICANT CONVECTION IS NOTED ON SATELLITE IMAGERY DUE LARGELY TO SAHARAN DUST THAT COVERS A LARGE AREA OF THE TROPICAL NORTH ATLC. TROPICAL WAVE EXTENDS FROM 08N74W TO 19N72W MOVING W AT 15 KT. THE WAVE COINCIDES WITH A SUBTLE 700 MB SHORTWAVE TROUGH AS PART OF A LARGER MID-LEVEL TROUGH ASSOCIATED WITH AN UPPER LEVEL LOW CENTERED OVER EASTERN CUBA. AS THE WAVE MOVES WEST AND COMES UNDER THE INFLUENCE OF THE DYNAMICS OF THE UPPER LEVEL LOW... SCATTERED MODERATE CONVECTION PERSISTS ACROSS A LARGE AREA FROM 15N-24N BETWEEN 62W-75W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 12N16W TO 09N33W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 09N33W TO 08N37W TO 05N53W. SCATTERED MODERATE CONVECTION IS FROM 03N-07N BETWEEN 20W-28W AND FROM 04N-11N BETWEEN 39W-43W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL RIDGE CENTERED OVER WEST TEXAS NEAR 33N101W CONTINUES TO BUILD IN OVER THE SE CONUS AND MUCH OF THE NORTHERN TWO-THIRDS OF THE GULF BASIN THIS MORNING. WATER VAPOR IMAGERY INDICATES MUCH OF THE NORTHEASTERLY FLOW ON THE SOUTHEASTERN PERIPHERY OF THE RIDGE ALOFT IS RELATIVELY DRY PROVIDING FOR AN OVERALL STABLE ENVIRONMENT AND QUIET CONDITIONS AT THE SURFACE FOR THE DAYTIME PERIOD AHEAD. HOWEVER A FEW ISOLATED SHOWERS AND TSTMS ARE OCCURRING ALONG A SURFACE TROUGH BOUNDARY EXTENDING FROM NORTHERN FLORIDA NEAR 30N83W TO 26N83W. OTHERWISE...A 1022 MB HIGH REMAINS ANCHORED NEAR 28N89W WHICH IS SLOWLY DRIFTING WESTWARD. GENTLE TO MODERATE ANTICYCLONIC WINDS ARE EXPECTED TO PERSIST THROUGH MONDAY INTO EARLY TUESDAY. CARIBBEAN SEA... NORTHWESTERLY FLOW ALOFT BECOMES MORE WESTERLY E OF 78W AS AN OVERALL STABLE ENVIRONMENT EXISTS OVER THE NW CARIBBEAN. A FEW ISOLATED SHOWERS ARE HOWEVER OCCURRING THIS MORNING FROM 18N-21N BETWEEN 79W-85W. THE WESTERLY FLOW LIES ON THE SOUTHERN PERIPHERY OF A VERY BROAD UPPER LEVEL LOW CENTERED OVER EASTERN CUBA. STRONG MIDDLE TO UPPER LEVEL DYNAMICS ASSOCIATED WITH THE LOW AND THE PRESENCE OF A TROPICAL WAVE ALONG 73W PROVIDING AMPLE LOW-LEVEL CONVERGENCE ARE GENERATING A LARGE AREA OF SCATTERED SHOWERS AND TSTMS ACROSS PORTIONS OF THE EASTERN AND CENTRAL CARIBBEAN FROM 13N-24N BETWEEN 62W-75W. MOISTURE FROM CONVECTION OCCURRING S OF 12N BETWEEN 75W-84W ACROSS THE SW CARIBBEAN AND COSTA RICA IS ALSO BEING ADVECTED INTO THE UPPER LEVEL LOW. WHILE THE UPPER LEVELS REMAIN FAIRLY DYNAMIC AND ACTIVE THROUGHOUT THE DAY SUNDAY...MODERATE TO FRESH TRADES PREVAIL WITH ONLY A SMALL AREA OF OCCASIONAL STRONG POSSIBLE WITHIN CLOSE PROXIMITY TO THE COAST OF COLOMBIA. THESE TRADES ARE EXPECTED TO PERSIST THROUGH TUESDAY. ...HISPANIOLA... A BROAD UPPER LEVEL LOW IS CENTERED OVER EASTERN CUBA PLACING THE ISLAND UNDER MAXIMUM MOIST SOUTHWESTERLY FLOW ALOFT THIS MORNING. GIVEN THE MIDDLE TO UPPER LEVEL DIFFLUENCE AND PRESENCE OF A TROPICAL WAVE ALONG 73W...SCATTERED SHOWERS AND TSTMS ARE OCCURRING ACROSS MUCH OF THE ISLAND THIS MORNING AND THIS ACTIVITY IS EXPECTED TO PERSIST THROUGHOUT THE DAY ON SUNDAY. THE UPPER LEVEL LOW IS FORECAST TO MOVE SLOWLY WEST-NORTHWEST LEAVING HISPANIOLA WITHIN THE AREA OF MAXIMUM DIFFLUENCE ALOFT THROUGH EARLY MONDAY RESULTING IN CONTINUED CONVECTION AND THE POSSIBILITY OF LOCALIZED FLOODING AND POSSIBLE MUDSLIDES. ATLANTIC OCEAN... AN UPPER LEVEL LOW IS CENTERED OVER EASTERN CUBA NEAR 21N75W SUPPORTING A BROAD AREA OF SCATTERED SHOWERS AND TSTMS ACROSS PORTIONS OF THE SW NORTH ATLC FROM 18N-24N BETWEEN 62W-76W. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A WEAK SURFACE RIDGE WITH AXIS ALONG 26N. TO THE NORTH OF THE AXIS...ALONG THE DISCUSSION AREA BORDER...A PAIR OF MID-LEVEL SHORTWAVE TROUGHS ARE NOTED ON WATER VAPOR IMAGERY... ONE NEAR 32N60W AND ANOTHER OFFSHORE OF THE NORTH CAROLINA COASTLINE NEAR 34N74W. BOTH SHORTWAVES SUPPORT LOW PRESSURE AREAS TO THE NORTH OF 32N...WITH A STATIONARY FRONT ANALYZED FROM 33N63W TO 33N71W. LOW-LEVEL MOISTURE CONTINUES TO POOL ALONG AND TO THE SOUTH OF THE STATIONARY FRONT GENERATING ISOLATED SHOWERS AND TSTMS N OF 28N BETWEEN 56W-72W...AND N OF 31N W OF 75W. FINALLY...THE CENTRAL AND EASTERN ATLC ARE DOMINATED BY AN INFLUENCE OF A SURFACE RIDGE ANCHORED BY A NEARLY STATIONARY 1027 MB HIGH CENTERED SE OF THE AZORES NEAR 37N24W AND A 1025 MB HIGH CENTERED NEAR 29N43W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN