000 AXNT20 KNHC 152341 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN JUL 15 2012 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 07N53W TO 15N55W MOVING W AT 15-20 KT. THE WAVE REMAINS DIFFICULT TO TRACK AS SAHARAN DUST CONTINUES TO SHROUD THE SIGNATURE OF THE WAVE AT THE SURFACE. TOTAL PRECIPITABLE WATER IMAGERY HAS CONTINUED TO FLATTEN OUT OVER THE PAST 24 HOURS DUE TO SYNOPTIC SCALE SURFACE RIDGING BETWEEN 50W-65W. NO SIGNIFICANT CONVECTION IS NOTED IN THE VICINITY OF THE WAVE. TROPICAL WAVE EXTENDS FROM 14N72W TO 21N72W MOVING W AT 20 KT. THE WAVE IS EMBEDDED WITHIN A NARROW AREA OF DEEP MOISTURE DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY BETWEEN 70W-75W ACROSS THE CENTRAL CARIBBEAN SEA. NO SIGNIFICANT CONVECTION IS NOTED ON SATELLITE IMAGERY THIS EVENING. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 13N17W TO 12N20W TO 11N37W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 11N37W TO 10N41W TO 05N52W. ISOLATED MODERATE CONVECTION IS FROM 08N-13N BETWEEN 14W-22W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL TROUGHING EXTENDS FROM AN UPPER LEVEL LOW CENTERED IN THE SW NORTH ATLC REGION NEAR 30N78W SOUTHWEST TO OVER A BROADER UPPER LEVEL LOW CENTERED NEAR 24N85W THAT INFLUENCES MUCH OF THE GULF OF MEXICO AND FLORIDA PENINSULA W OF 93W. MOST OF THE SIGNIFICANT MIDDLE TO UPPER LEVEL LIFT ASSOCIATED WITH THIS UPPER LEVEL LOW IS EAST OF 86W WITH SCATTERED SHOWERS AND TSTMS OCCURRING THIS EVENING E OF 85W AND ACROSS THE FLORIDA PENINSULA AND FLORIDA STRAITS. A WEAK SURFACE TROUGH IS ENHANCING THIS CONVECTION ANALYZED FROM NEAR JACKSONVILLE TO 26N84W. ANOTHER WEAK SURFACE TROUGH IS ANALYZED ALONG 90W FROM THE NORTHERN YUCATAN PENINSULA NEAR 20N TO 28N WITH ISOLATED SHOWERS AND TSTMS OCCURRING OVER THE CENTRAL GULF BETWEEN 88W-94W. ELSEWHERE ACROSS THE REMAINDER OF THE FAR WESTERN GULF...A WEAKENING SURFACE RIDGE AXIS EXTENDS FROM WEST OF THE SURFACE TROUGH ALONG 90W NEAR 27N94W TO A 1018 MB HIGH CENTERED OVER COASTAL EAST-CENTRAL MEXICO NEAR 20N97W. A FEW ISOLATED SHOWERS AND TSTMS ARE OCCURRING FROM 21N-24N BETWEEN 96W-98W ON LIGHT EAST-SOUTHEASTERLY FLOW BETWEEN THE TROUGHING ACROSS THE CENTRAL GULF AND HIGHER PRESSURE OVER MEXICO. CARIBBEAN SEA... A BROAD UPPER LEVEL LOW CENTERED OVER THE SE GULF OF MEXICO NEAR 24N85W IS PROVIDING THE NW CARIBBEAN N OF 17N W OF 75W WITH SOUTHWEST TO WESTERLY FLOW ALOFT. WITH MUCH OF THE INSTABILITY LOCATED IN CLOSER PROXIMITY TO THE UPPER LEVEL LOW...SCATTERED SHOWERS AND TSTMS ARE OCCURRING OVER PORTIONS OF THE EASTERN YUCATAN PENINSULA AND ADJACENT COASTAL WATERS...WESTERN CUBA N OF 22N BETWEEN 79W-85W...AND OVER FAR EASTERN CUBA N OF 20N BETWEEN 74W-76W. OVER THE REMAINDER OF THE CARIBBEAN BASIN...AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED NEAR 13N76W AND STRETCHES INFLUENCE FROM 60W TO AS FAR WEST AS 93W OVER PORTIONS OF CENTRAL AMERICA AND THE EAST PACIFIC REGION. LOW-LEVEL MOISTURE CONVERGENCE ALONG WITH MAXIMIZED UPPER LEVEL DIFFLUENCE DUE TO THE UPPER LEVEL ANTICYCLONE IS GENERATING A LARGE AREA OF SCATTERED SHOWERS AND TSTMS FROM 10N-17N BETWEEN 81W-86W. THIS AREA OF MOISTURE AND CONVECTIVE ACTIVITY IS EXPECTED TO CONTINUE TRACKING WESTWARD THROUGH THE OVERNIGHT HOURS INTO MONDAY WITH THE POTENTIAL FOR LOCALIZED HEAVY RAINFALL ACROSS NICARAGUA AND HONDURAS. THE REST OF THE CARIBBEAN E OF 75W IS FAIRLY TRANQUIL THIS EVENING. THE TROPICAL WAVES ALONG 73W AND APPROACHING WAVE ALONG 55W CARRY LITTLE SIGNIFICANT MOISTURE AND CONVECTION DUE TO THE PRESENCE OF SUSPENDED SAHARAN DUST THAT EXTENDS TO ALMOST 72W THIS EVENING. SURFACE RIDGING FROM THE CENTRAL ATLC ALSO DIPS SOUTHWARD ACROSS PORTIONS OF THE NE CARIBBEAN PROVIDING FOR OVERALL STABLE AND FAIR WEATHER. ATLANTIC OCEAN... UPPER LEVEL TROUGHING EXTENDS ACROSS MUCH OF THE SW NORTH ATLC W OF 72W WITH AN UPPER LEVEL LOW CENTERED NEAR 30N78W TO ANOTHER UPPER LEVEL LOW CENTERED OVER THE SE GULF OF MEXICO NEAR 24N85W. THIS TROUGHING IS RESULTING IN WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS OVER MUCH OF THE SW NORTH ATLC W OF 73W THIS EVENING AND MORE AREAL COVERAGE OF SHOWERS AND TSTMS ACROSS THE FLORIDA PENINSULA. FARTHER EAST...A LARGE AREA OF HIGH PRESSURE DOMINATES THE CENTRAL ATLC ANCHORED BY A 1024 MB HIGH CENTERED SE OF BERMUDA NEAR 29N62W. A SMALL COMPLEX OF SHOWERS AND TSTMS IS CENTERED NEAR 29N56W AND REMAINS ENHANCED WITHIN A WEAKNESS OF THE SURFACE RIDGE AND MAXIMUM MIDDLE TO UPPER LEVEL DIFFLUENCE. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF SURFACE RIDGING EXTENDING FROM A 1027 MB HIGH CENTERED WEST OF THE IBERIAN PENINSULA NEAR 42N17W TO A 1023 MB HIGH CENTERED NEAR 32N46W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN