000 AXNT20 KNHC 051746 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN JUL 05 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... ...GALE IN THE CARIBBEAN... A GALE WARNING IS IN EFFECT FOR THE SW CARIBBEAN FROM 11N TO 13.5N BETWEEN 73W AND 78W THROUGH MONDAY MORNING. THESE WINDS ARE GENERATED BY A TIGHT PRESSURE GRADIENT BETWEEN THE STRONG SURFACE RIDGE OVER THE ATLC AND LOW PRESSURE OVER COLOMBIA. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE OVER THE CENTRAL TROPICAL ATLC EXTENDS ALONG 45W FROM 5N TO 15N MOVING W NEAR 25 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED WITHIN AN SURGE OF MODERATE MOISTURE S OF 12N. ENHANCED METEOSAT IMAGERY SHOWS SAHARAN DUST ACROSS THE NORTHERN PORTION OF THE WAVE. ISOLATED MODERATE CONVECTION IS FROM 06N TO 09N BETWEEN 43W AND 48W. THIS CONVECTION IS PARTIALLY ASSOCIATED WITH THE SURROUNDING ITCZ. TROPICAL WAVE IN THE W TROPICAL ATLC EXTENDS ALONG 54W FROM 6N TO 15N MOVING W NEAR 20 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED WITHIN DEEP HIGH MOISTURE S OF 12N. DRY SAHARAN AIR IS NORTH OF 12N. SCATTERED MODERATE CONVECTION IS FROM 06N TO 11N BETWEEN 52W AND 56W. THIS CONVECTION IS PARTIALLY ASSOCIATED WITH THE SURROUNDING ITCZ. TROPICAL WAVE IN THE WESTERN CARIBBEAN EXTENDS ALONG 82W/83W FROM 10N TO 19N MOVING W AT AROUND 20 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE WATER IMAGERY SHOWS THE WAVE IS EMBEDDED WITHIN A SURGE OF MODERATE TO DEEP MOISTURE. ISOLATED MODERATE CONVECTION IS FROM 15N TO 19N BETWEEN 82W AND 86W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE TROPICAL ATLC NEAR 19N16W ALONG 14N20W TO 8N24W WHERE THE ITCZ BEGINS AND CONTINUES TO 07N44W...THEN RESUMES W OF THE CENTRAL ATLC TROPICAL WAVE NEAR 8N47W TO 08N53W...THEN RESUMES AGAIN W OF THE WESTERN ATLC WAVE NEAR 8N56W TO THE S AMERICA COAST NEAR 09N62W. ISOLATED MODERATE CONVECTION IS WITHIN 50 NM OF THE ITCZ AXIS BETWEEN 28N AND 48W. SCATTERED MODERATE CONVECTION IS WITHIN 125 NM OF THE ITCZ AXIS W OF 48W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LOW IS CENTERED OVER THE SOUTHERN GULF NEAR 23N87W WITH THE BASE OF AN UPPER TROUGH EXTENDING FROM THE TENNESSEE VALLEY TO THE NE GULF. UPPER LEVEL DIFFLUENCE BETWEEN THESE TWO UPPER LEVEL FEATURES AND LIFT ASSOCIATED WITH THE TROUGH SUPPORTS CLUSTERS OF MODERATE TO STRONG CONVECTION FROM 28N TO THE N GULF COAST BETWEEN 84W AND 90W. AT THE SURFACE...A RIDGE AXIS EXTENDS ACROSS CENTRAL FL AND OVER THE NORTHERN GULF TO THE TX GULF COAST. S TO SE WINDS OF 10 TO 15 KT COVER THE GULF S OF 27N. S TO SW WINDS OF 5 TO 15 KT COVER THE GULF N OF 27N...WITH THE LIGHTEST WINDS OVER THE NE GULF AWAY FROM THE CONVECTION. EXPECT CONVECTION TO DECREASE OVER THE NE GULF TONIGHT WITH MAINLY ISOLATED TO SCATTERED WEAK CONVECTION OVER THE EASTERN GULF ON MONDAY. CARIBBEAN SEA... THE UPPER LOW OVER THE SOUTHERN GULF OF MEXICO IS SUPPORTING SCATTERED THUNDERSTORMS N OF 16N AND W OF 85W OVER THE NW CARIBBEAN. A TROPICAL WAVE IS OVER THE SW CARIBBEAN. PLEASE SEE THE TROPICAL WAVES SECTION FOR MORE DETAILS. ENHANCED METEOSAT IMAGERY INDICATES THE THE CENTRAL AND EASTERN CARIBBEAN IS COVERED IN A SAHARAN AIR LAYER WITH DUST. THIS...COMBINED WITH DRY AIR AND SHEAR IS INHIBITING CONVECTION ACROSS THIS PORTION OF THE BASIN. A STRONG PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE SUBTROPICAL NORTHERN ATLC AND LOWER PRESSURES OVER S AMERICA SUPPORTS WINDS OF 20 TO 30 KT FROM 10N TO 18N BETWEEN 63W AND 82W WITH GALE FORCE WINDS OVER A PORTION OF THE SW CARIBBEAN. PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. THE PRESSURE GRADIENT WILL WEAKEN SLIGHTLY ON MONDAY AS THE HIGH OVER THE ATLC ERODES FROM THE WEST WITH THE APPROACH OF AN UPPER TROUGH. THIS WILL BE SUFFICIENT TO BRING WINDS BELOW GALE FORCE OVER THE SW CARIBBEAN BY LATE MONDAY MORNING. A TROPICAL WAVE WILL MOVE OVER THE LEEWARD ISLANDS ON MONDAY. EXPECT CONVECTION ACROSS THE SOUTHERN LEEWARD ISLANDS LATE TODAY THROUGH MONDAY. ...HISPANIOLA... DRY AIR AND SAHARAN DUST ARE OVER THE ISLAND TODAY. CANNOT RULE OUT AN ISOLATED THUNDERSTORM OVER THE INLAND MOUNTAINS THIS AFTERNOON AND EARLY EVENING. OTHERWISE...FAIR CONDITIONS ARE EXPECTED. A TROPICAL WAVE APPROACHING FROM THE EAST MAY BRING AN INCREASE IN SHOWER AND THUNDERSTORM COVERAGE BY LATE MONDAY. ATLANTIC OCEAN... AN UPPER RIDGE AXIS EXTENDS FROM THE CARIBBEAN AND OVER THE NORTHERN BAHAMAS TO THE CAROLINA COASTS. DIFFLUENCE ASSOCIATED WITH THIS RIDGE SUPPORTS ISOLATED MODERATE CONVECTION AND THUNDERSTORMS FROM 27N TO 31N BETWEEN 78W AND 80W. AN UPPER LOW CENTERED NEAR 27N69W SUPPORTS ISOLATED MODERATE CONVECTION AND THUNDERSTORMS FROM 27N TO 31N BETWEEN 63W AND 69W. A SURFACE TROUGH EXTENDS FROM 29N57W TO 25N58W. ISOLATED MODERATE CONVECTION IS FROM 27N TO 31N BETWEEN 55W AND 58W. A 1029 MB HIGH CENTERED NEAR 34N41W ANCHORS SURFACE RIDGING THAT COVERS THE MAJORITY OF THE SUBTROPICAL NORTHERN ATLC. TWO TROPICAL WAVES ARE OVER THE TROPICAL NORTHERN ATLC. PLEASE SEE THE TROPICAL WAVES SECTION FOR MORE DETAILS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO