000 AXNT20 KNHC 190601 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN JUL 19 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 0515 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 04N35W TO 17N31W MOVING W AT 15-20 KT. THE WAVE COINCIDES WITH A BROAD 700 MB TROUGH BETWEEN 26W- 37W. SSMI TPW INDICATES MODERATE MOISTURE S OF 12N ALONG THE WAVE. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 05N-09N BETWEEN 35W-39W. TROPICAL WAVE EXTENDS FROM 08N46W TO 20N46W MOVING W AT 20 KT. THIS WAVE ALSO COINCIDES WITH A BROAD 700 MB TROUGH BETWEEN 44W- 50W. SSMI TPW INDICATES A POLEWARD SURGE OF HIGH MOISTURE ALONG THE WAVE AXIS. ISOLATED MODERATE CONVECTION IS FROM 09N-16N BETWEEN 45W-52W. TROPICAL WAVE EXTENDS FROM 05N56W TO 21N52W MOVING W AT 15-20 KT. THE WAVE COINCIDES WITH A TILTED 700 MB TROUGH BETWEEN 54W- 61W. DRY AIR AND SAHARAN DUST IS EVIDENT IN THE ENVIRONMENT OF THE WAVE...INHIBITING CONVECTION ALONG THE WAVE. TROPICAL WAVE HAS MOVED INLAND OVER THE YUCATAN TO GUATEMALA AND OVER THE EASTERN PACIFIC. PLEASE REFER TO THE PACIFIC TROPICAL WEATHER DISCUSSION AT MIATWOEP FOR ADDITIONAL DETAILS. ...ITCZ/MONSOON TROUGH... THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N35W TO 05N51W. ASIDE FROM CONVECTION ASSOCIATED WITH THE EASTERNMOST TROPICAL WAVE...WIDELY SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 08N BETWEEN 37W AND 48W. ...DISCUSSION... GULF OF MEXICO... NORTHEASTERLY FLOW ALOFT PERSISTS ACROSS THE MAJORITY OF THE GULF AROUND RIDGING THAT EXTENDS FROM THE TX COAST TO THE TN VALLEY. A WEAKNESS IN THIS RIDGE OVER THE NE GULF CONTINUES TO SUPPORT A SURFACE TROUGH THAT EXTENDS FROM THE FL PANHANDLE NEAR TALLAHASSEE TO 30N85W TO 28N87W TO 27N90W. SCATTERED SHOWERS ARE OCCURRING WITHIN 150 NM OF THE TROUGH AXIS. ADDITIONAL SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OVER THE SE GULF FROM 24N TO 28N E OF 86W AND ARE PRIMARILY BEING DRIVEN BY WEAK PERTURBATIONS IN THE NE FLOW ALOFT AND DEEP TROPICAL MOISTURE IN PLACE ACROSS THE AREA. SURFACE RIDGING ANCHORED BY A 1018 MB HIGH CENTERED NEAR 27N91W SUPPORTS GENERALLY FAIR WEATHER ACROSS THE REMAINDER OF THE GULF BASIN. A DIURNALLY DRIVEN SURFACE TROUGH IS ALONG THE WESTERN COAST OF THE YUCATAN FROM 21N90W TO 18N91W. CURRENTLY THERE IS NO DEEP CONVECTION NOTED WITH THIS TROUGH. OVER THE NEXT 24 HOURS SURFACE TROUGHING IS EXPECTED TO PERSIST OVER THE NE GULF WITH ONGOING CONVECTION POSSIBLE OVER THAT PORTION OF THE BASIN. PERIODIC CONVECTION WILL BE POSSIBLE OVER THE SW GULF IN THE VICINITY OF THE YUCATAN DRIVEN SURFACE TROUGH. CARIBBEAN SEA... NORTHEASTERLY FLOW ALOFT COVERS THE NW CARIBBEAN AROUND THE PERIPHERY OF THE TX UPPER LEVEL RIDGE...WITH S TO SE FLOW ALOFT OVER THE EASTERN CARIBBEAN AROUND A CENTRAL TROPICAL ATLC UPPER LEVEL RIDGE. IN BETWEEN...TROUGHING THAT EXTENDS FROM THE W ATLC TO THE SW CARIBBEAN SUPPORTS A BROAD AREA OF WEAK UPPER LEVEL DIFFLUENCE THAT SPANS FROM CUBA AND HISPANIOLA SW TO NICARAGUA AND THE SW CARIBBEAN. THIS DIFFLUENCE COMBINED WITH MODERATE TO HIGH ATMOSPHERIC MOISTURE SUPPORTS SCATTERED THUNDERSTORMS FROM 18N TO 23N BETWEEN 72W AND 85W...INCLUDING THE CAYMAN ISLANDS. SCATTERED MODERATE CONVECTION IS S OF 15N W OF 75W OVER THE SW CARIBBEAN. 15 TO 20 KT TRADE WINDS COVER THE MAJORITY OF THE CARIBBEAN WITH A SMALL AREA OF WINDS TO 25 KT N OF THE COLOMBIA COAST...WHERE THE PRESSURE GRADIENT IS TIGHTEST BETWEEN ATLC HIGH PRESSURE AND LOWER PRESSURE OVER COLOMBIA. OVER THE NEXT 24 HOURS CONVECTION WILL BE POSSIBLE OVER THE SW AND WESTERN CARIBBEAN UNDER DIFFLUENT FLOW IN THE PRESENCE OF DEEP MOISTURE. ...HISPANIOLA... DIFFLUENCE ALOFT IS SUPPORTING ISOLATED THUNDERSTORMS OVER THE EXTREME W PORTION OF HAITI THIS MORNING. THESE STORMS SHOULD DIMINISH LATER THIS MORNING. DRY IN PLACE IS EXPECTED TO INHIBIT SHOWER AND THUNDERSTORM ACTIVITY ELSEWHERE OVER THE ISLAND THROUGH TONIGHT. ATLANTIC OCEAN... UPPER LEVEL RIDGING EXTENDS FROM THE US INTO THE W ATLC WITH MID TO UPPER LEVEL DISTURBANCES EVIDENT IN WATER VAPOR IMAGERY ROUNDING THE PERIPHERY OF THE RIDGING W OF 75W AROUND 30N...SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS FROM 29N TO 31N BETWEEN 74W AND 80W. A PAIR OF UPPER LOWS CENTERED NEAR 29N68W AND 28N57W SUPPORT ISOLATED THUNDERSTORMS N OF 24N BETWEEN 54W AND 72W. A SURFACE TROUGH IS A REFLECTION OF THE EASTERNMOST UPPER LOW AND EXTENDS FROM 30N55W TO 27N60W TO 25N65W. THIS TROUGH ALSO ACTS AS A WEAKNESS IN THE SUBTROPICAL RIDGE WITH A 1021 MB HIGH CENTERED NEAR 29N65W. A 1025 MB HIGH CENTERED NEAR 29N40W ANCHORS RIDGING THAT EXTENDS ACROSS THE CENTRAL AND EASTERN SUBTROPICAL ATLC. THREE TROPICAL WAVES ARE OVER THE TROPICAL NORTHERN ATLC. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. EXPECT CONVECTION TO CONTINUE ALONG 30N OFF THE FL COAST OVER THE NEXT 24 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO