000 AXNT20 KNHC 160538 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0530 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS APPROXIMATELY ALONG 34W FROM 09N 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 THE WAVE MAINLY ALONG THE NORTHERN HALF OF IT WHICH REMAINS CONVECTION-FREE. SCATTERED MODERATE CONVECTION IS S OF 12N BETWEEN 31W-35W SUPPORTED BY UPPER-LEVEL DIVERGENCE. A LARGE AMPLITUDE TROPICAL WAVE IS MOVING OVER THE WINDWARD ISLANDS WITH AXIS APPROXIMATELY ALONG 61W BETWEEN 06N AND 20N ...MOVING AT 20 KT. SSMI TPW AND METEOSAT IMAGERY DEPICT A MODERATELY MOIST ENVIRONMENT SURROUNDING THIS WAVE BUT UPPER- LEVEL SUBSIDENCE AND SAHARAN DUST ARE KEEPING THIS AREA WITHOUT ANY SIGNIFICANT CONVECTION AT THIS TIME. A TROPICAL WAVE IS OVER THE W CARIBBEAN WITH AXIS APPROXIMATELY ALONG 79W BETWEEN 11N AND 18N...MOVING W AT 15-20 KT. SSMI TPW IMAGERY INDICATE THE WAVE IS EMBEDDED IN A MODERATELY MOIST ENVIRONMENT. A DIFFLUENT FLOW ALOFT IS SUPPORTING CLOUDINESS AND ISOLATED CONVECTION OVER THE NORTHERN PORTION OF THE WAVE N OF 16N WHILE THE PRESENCE OF THE MONSOON TROUGH AXIS OVER THE SOUTHERN PORTION OF THE WAVE IS SUPPORTING SCATTERED MODERATE CONVECTION S OF 11N. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH ENTERS THE ATLANTIC OCEAN THROUGH GUINEA BISSAU NEAR 13N17W CONTINUING TO 12N19W. THE ITCZ EXTENDS FROM THAT POINT TO 11N30W THEN RESUMES W OF A TROPICAL WAVE NEAR 10N35W TO 06N47W TO 08N59W. ASIDE FROM THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS OBSERVED FROM 05N-12N BETWEEN 35W-43W. ...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 1016 MB SURFACE HIGH IS CENTERED NEAR 26N88W. A WEAK SURFACE TROUGH IS OVER THE BAY OF CAMPECHE EXTENDING FROM 22N95W TO 18N94W. THE CONVECTION OF A SQUALL LINE THAT CURRENTLY IS MOVING OVER MISSISSIPPI AND ALABAMA IS REACHING THE NE GULF MAINLY N OF 28N. ALOFT...AN ELONGATED UPPER-LEVEL LOW IS CENTERED OVER THE ISTHMUS OF TEHUANTEPEC EXTENDS INTO THE BAY OF CAMPECHE PROVIDING SUPPORTING SCATTERED CONVECTION S OF 21N BETWEEN 91W-95W. A MID TO UPPER-LEVEL ANTICYCLONE OVER E TEXAS WITH RIDGE AXIS EXTENDING 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. OVER THE SW CARIBBEAN...THE PRESENCE OF THE MONSOON TROUGH SUPPORTS SCATTERED MODERATE CONVECTION S OF 11N BETWEEN 75W-80W. A SAHARAN AIRMASS ENGULFING THE NEXT TROPICAL WAVE TO ENTER THE BASIN COVERS THE E CARIBBEAN E OF 70W...THUS INHIBITING CONVECTION. SCATTEROMETER DATA DEPICTS LIGHT TO GENTLE TRADES ACROSS THE W CARIBBEAN W OF 80W. A PRESSURE GRADIENT BETWEEN 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. FRESH TRADES PREVAIL ACROSS THE BASIN MAINLY E OF 80W. THE NEXT TROPICAL WAVE WILL ENTER THE E CARIBBEAN TONIGHT POSSIBLY 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 PUERTO RICO AND THE DOMINICAN REPUBLIC AND UPPER-LEVEL SUBSIDENCE ALSO PREVAILS OVER THIS AREA. THIS WILL LIMIT CONVECTION OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... TWO TROPICAL WAVES ARE OVER THE TROPICAL ATLANTIC ALONG 32W AND 59W. PLEASE SEE THE TROPICAL WAVES SECTION ABOVE FOR MORE DETAILS. THE BASE OF AN UPPER-LEVEL TROUGH ALONG THE EASTERN CONUS AND THE PRESENCE OF AN UPPER-LEVEL LOW OVER THE BAHAMAS IS GENERATING DIFFLUENT FLOW W OF 70W. WITH THIS...CLOUDINESS AND ISOLATED CONVECTION PREVAILS ACROSS THE W ATLANTIC. 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 35N41W WITH ISOLATED CONVECTION ALONG IT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ ERA