000 AXNT20 KNHC 161035 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU JUL 16 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 1030 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS APPROXIMATELY ALONG 36W FROM 08N TO 19N MOVING W AT 20-25 KT. TPW IMAGERY INDICATES THE WAVE IS EMBEDDED IN A DEEP MOIST ENVIRONMENT MAINLY E OF THE WAVE AXIS. METEOSAT SAL IMAGERY SHOW SAHARAN DRY AIR ALSO IN THE ENVIRONMENT OF THIS WAVE ALONG THE NORTHERN HALF OF IT WHICH REMAINS CONVECTION-FREE. SCATTERED MODERATE CONVECTION IS S OF 13N BETWEEN 30W-40W SUPPORTED BY UPPER-LEVEL DIVERGENCE AND THE PROXIMITY OF THE ITCZ AT THE SURFACE. A TROPICAL WAVE IS MOVING OVER THE E CARIBBEAN WITH AXIS APPROXIMATELY ALONG 64W BETWEEN 06N AND 20N...MOVING AT 20 KT. SSMI TPW AND METEOSAT IMAGERY DEPICT A MODERATELY MOIST ENVIRONMENT SURROUNDING THIS WAVE BUT A STRONG DEEP-LAYER WIND SHEAR AND SAHARAN DUST ARE KEEPING THIS AREA WITHOUT ANY SIGNIFICANT CONVECTION...ONLY ISOLATED SHOWERS FROM 15N-17N BETWEEN 65W-69W. A TROPICAL WAVE IS OVER THE W CARIBBEAN WITH AXIS ALONG 82W BETWEEN 10N AND 19N...MOVING W AT 15 KT. SSMI TPW IMAGERY INDICATE THE WAVE IS EMBEDDED IN A MODERATELY MOIST ENVIRONMENT. SCATTERED CONVECTION PREVAILS IN THE ENVIRONMENT OF THIS WAVE MAINLY W OF 81W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH ENTERS THE ATLANTIC OCEAN THROUGH GUINEA BISSAU NEAR 14N17W CONTINUING TO 12N21W. THE ITCZ EXTENDS FROM THAT POINT TO 11N34W THEN RESUMES W OF A TROPICAL WAVE NEAR 10N38W TO 08N59W. ASIDE FROM THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...ISOLATED MODERATE CONVECTION IS OBSERVED S OF THE ITCZ AXIS MAINLY W OF 56W AFFECTING PORTIONS OF GUYANA. ...DISCUSSION... GULF OF MEXICO... A BROAD SURFACE RIDGE COVERS A LARGE PORTION OF THE ATLANTIC BASIN AND EXTENDS WESTWARD ACROSS SOUTH FLORIDA AND THE STRAITS OF FLORIDA REACHING THE GULF OF MEXICO. A WEAK 1017 MB SURFACE HIGH IS CENTERED NEAR 25N84W. A SURFACE TROUGH IS OVER THE BAY OF CAMPECHE EXTENDING FROM 23N96W TO 20N96W. ALOFT...AN ELONGATED UPPER-LEVEL LOW IS CENTERED OVER THE ISTHMUS OF TEHUANTEPEC AND EXTENDS INTO THE BAY OF CAMPECHE SUPPORTING SCATTERED CONVECTION S OF 20N BETWEEN 93W-96W. A MID TO UPPER- LEVEL ANTICYCLONE OVER E TEXAS WITH RIDGE AXIS EXTENDS SE ACROSS THE GULF TO NORTHERN FLORIDA. DEEP LAYERED SUBSIDENCE PREVAILS OVER THE NW GULF SUPPORTING FAIR WEATHER. SCATTEROMETER DATA DEPICTS A LIGHT ANTICYCLONIC FLOW PREVAILING ACROSS THE BASIN. SURFACE RIDGING AND LIGHT FLOW WILL BE THE DOMINANT FEATURE DURING THE NEXT FEW DAYS. CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE W CARIBBEAN. PLEASE REFER TO THE SECTION ABOVE FOR MORE DETAILS. STRONG DEEP LAYER WIND SHEAR INHIBITS CONVECTION ACROSS THE MAJORITY OF THE BASIN. UPPER LEVEL DIFFLUENCE PREVAILS ACROSS CENTRAL AMERICA WHICH SUPPORTS SCATTERED MODERATE CONVECTION THAT IS CURRENTLY REACHING THE W CARIBBEAN W OF 83W. OVER THE S-CENTRAL CARIBBEAN...THE PRESENCE OF THE MONSOON TROUGH N OF PANAMA SUPPORTS ISOLATED MODERATE CONVECTION S OF 11N. A SAHARAN AIRMASS ENGULFING THE NEXT TROPICAL WAVE TO ENTER THE BASIN COVERS THE E CARIBBEAN E OF 70W...THUS INHIBITING SIGNIFICANT CONVECTION. SCATTEROMETER DATA DEPICTS LIGHT TO GENTLE TRADES ACROSS THE W CARIBBEAN W OF 80W. A PRESSURE GRADIENT BETWEEN THE RIDGE OF HIGH PRESSURE OVER THE ATLANTIC EXTENDING ACROSS THE NORTHERN BASIN AND LOWER PRESSURE OVER SOUTH AMERICA SUPPORTS FRESH TO STRONG TRADE WINDS ACROSS THE CENTRAL CARIBBEAN MAINLY S OF 16N BETWEEN 70W-79W. MODERATE TO FRESH TRADES PREVAIL ACROSS THE REMAINDER OF THE BASIN MAINLY E OF 80W. THE NEXT TROPICAL WAVE WILL ENTER THE E CARIBBEAN TONIGHT INCREASING MOISTURE AND ENHANCING SHOWERS OVER THE LESSER ANTILLES AND PUERTO RICO. HISPANIOLA... FAIR WEATHER PREVAILS ACROSS THE ISLAND AT THIS TIME. TPW IMAGERY DEPICTS A PATCH OF DRIER AIR OVER W PUERTO RICO AND THE DOMINICAN REPUBLIC. UPPER-LEVEL SUBSIDENCE ALSO PREVAILS OVER THIS AREA INHIBITING CONVECTION. THIS PATTERN WILL CONTINUE OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... TWO TROPICAL WAVES ARE OVER THE TROPICAL ATLANTIC ALONG 36W AND 64W. PLEASE SEE THE TROPICAL WAVES SECTION ABOVE FOR MORE DETAILS. AN UPPER-LEVEL TROUGH ALONG THE E US COAST AND THE PRESENCE OF AN UPPER-LEVEL LOW OVER THE BAHAMAS ARE GENERATING A DIFFLUENT FLOW ACROSS THE W ATLANTIC W OF 70W. WITH THIS...CLOUDINESS AND ISOLATED CONVECTION PREVAIL ACROSS W OF 70W. THE BERMUDA AZORES HIGH EXTENDS A RIDGE ACROSS THE CENTRAL AND E TROPICAL ATLANTIC SUPPORTING FAIR WEATHER. A SURFACE TROUGH EXTENDS OVER THE N-CENTRAL ATLANTIC FROM 27N54W TO 34N42W WITH ISOLATED CONVECTION ALONG IT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA