000 AXNT20 KNHC 050540 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI SEP 05 2014 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 ASSOCIATED WITH A 1009 MB LOW PRESSURE CENTER IS ABOUT 170 NM EAST OF THE CAPE VERDE ISLANDS. ITS AXIS EXTENDS FROM 18N20W TO THE LOW NEAR 14N21W TO 08N21W...MOVING WEST AT 10- 15 KT. SSMI TOTAL PRECIPITABLE WATER VAPOR IMAGERY SHOWS A MOIST ENVIRONMENT MAINLY N OF THE LOW FROM 14N-18N BETWEEN 17W-25W. A CLUSTER OF MODERATE CONVECTION IS FROM 11N-16N BETWEEN 22W- 25W...COINCIDING WITH A REGION OF DEEP LAYER HIGH MOISTURE. A TROPICAL WAVE IS ON THE CENTRAL ATLANTIC WITH AXIS EXTENDING FROM 16N46W TO 09N46W...MOVING W AT 10-15 KT. MODERATE LOW-LEVEL MOISTURE IS ASSOCIATED WITH THE WAVE WITH SOME SAHARAN DRY AIR AFFECTING ITS NORTHERN ENVIRONMENT. STRONG DEEP LAYER ENVIRONMENTAL WIND SHEAR IN ITS REGION IS HINDERING CONVECTIVE ACTIVITY. DESPITE THIS...ISOLATED TSTMS ARE DEVELOPING IN THE VICINITY OF THIS WAVE ALONG 14N...BETWEEN 45W-50W. A TROPICAL WAVE IS OVER THE EASTERN CARIBBEAN WITH AXIS AT ABOUT 20 NM E OF VIEQUES...PUERTO RICO. THIS AXIS EXTENDS FROM 21N65W TO 11N66W...AND ITS MOVING W AT 15-20 KT. MAINLY MODERATE LOW- LEVEL MOISTURE IS ASSOCIATED WITH THE WAVE...WHICH ALONG UPPER- LEVEL DIFFLUENCE SUPPORT SCATTERED MODERATE CONVECTION ACROSS THE E CARIBBEAN AND THE COASTAL WATERS N OF PUERTO RICO FROM 16N- 20N BETWEEN 63W-67W. A TROPICAL WAVE IS ON THE CENTRAL CARIBBEAN WITH AXIS MOVING ACROSS EASTERN CUBA FROM 21N74W TO 12N75W...MOVING W AT 10-15 KT. SSMI TOTAL PRECIPITABLE WATER VAPOR IMAGERY SHOW MODERATE/HIGH MOISTURE IN ITS SOUTHERN ENVIRONMENT S OF 15N WITH A SLOT OF DRIER AIR NORTHWARD. STRONG DEEP LAYER ENVIRONMENTAL SHEAR IN THE REGION IS INHIBITING THE DEVELOPMENT OF CONVECTION NEARBY THE WAVE AXIS. A FEW CLUSTERS OF MODERATE TO STRONG CONVECTION REMAIN W OF THE WAVE AXIS ALONG 19N...76W-79W. A TROPICAL WAVE CONTINUES OVER THE YUCATAN PENINSULA...WITH AXIS EXTENDING FROM 21N90W TO 12N90W. THIS WAVE IS MOVING W AT 15-20 KT. SCATTERED MODERATE CONVECTION REMAIN ACROSS THE SOUTHERN PORTION OF THE WAVE AXIS S OF 17N AND EXTENDING TO THE COASTAL WATERS OF GUATEMALA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 17N16W TO 07N27W TO 07N33W. THE ITCZ EXTENDS FROM 07N33W TO 10N52W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE SECTION...ISOLATED MODERATE CONVECTION IS ALONG 10N...BETWEEN 46W-54W. ...DISCUSSION... GULF OF MEXICO... NUMEROUS SHOWERS AND TSTMS ARE OVER THE COAST OF MEXICO MAINLY W OF 97W. SOME OF THIS ACTIVITY COULD MOVE TO THE WESTERN GULF WATERS. ISOLATED CONVECTION CONTINUES IN THE VICINITY OF A SURFACE TROUGH THAT EXTENDS TO THE EASTERN GULF FROM 25N-27N BETWEEN 82W-84W. AN ELONGATED UPPER LEVEL LOW WITH CENTER ACROSS THE WESTERN CARIBBEAN NEAR 28N68W COUPLED WITH AN UPPER LEVEL HIGH ACROSS SOUTH CAROLINA NEAR 34N80W ARE SUPPORTING THE DIFFLUENT ENVIRONMENT ACROSS THE EASTERN GULF. WEAK SURFACE RIDGING PREVAILS ACROSS THE GULF...THUS PROVIDING E-SE WIND FLOW OF 5-10 KT. THE TROPICAL WAVE WILL ENTER THE BAY OF CAMPECHE FRIDAY THROUGH SATURDAY THEN WILL MOVE INLAND MEXICO. NO MAJOR CHANGES ELSEWHERE. CARIBBEAN SEA... TWO TROPICAL WAVES ARE ACROSS THE REGION...ONE OVER THE EASTERN CARIBBEAN AND ANOTHER MOVING ACROSS THE WINDWARD PASSAGE. THE LATTER CONTINUES TO ENHANCE SCATTERED MODERATE CONVECTION ACROSS THE COASTAL WATERS S OF CUBA ALONG 20N...BETWEEN 75W-80W. SEE THE TROPICAL WAVES SECTION ABOVE FOR MORE DETAILS. MODERATE MOISTURE OVER WESTERN CUBA AS WELL AS A DIFFLUENT ENVIRONMENT BEING GENERATED BY AN UPPER-LEVEL RIDGE CENTERED OVER SOUTH CAROLINA AND AN ELONGATED UPPER-LEVEL LOW LOCATED ON THE W CARIBBEAN. IN THE SW BASIN...DEEP LAYER MOISTURE ALONG WITH A DIFFLUENT ENVIRONMENT GENERATED BY AN UPPER-LEVEL RIDGE ON THE CENTRAL CARIBBEAN ARE SUPPORTING THE GENERATION OF NUMEROUS CLUSTERS OF MODERATE TO STRONG CONVECTION S OF 16N WEST OF 79W. TRADES OF 15 KT ABOUNDS ACROSS THE BASIN...EXCEPT ON THE CENTRAL CARIBBEAN WHERE WINDS INCREASE TO 20-25 KT DUE TO A TIGHTER PRESSURE GRADIENT AND THE PASSAGE OF THE TROPICAL WAVE. SHOWERS WILL CONTINUE IN THE SW BASIN...EXTENDING TO THE NW THROUGH LATE SATURDAY. A NEW TROPICAL WAVE WILL MOVE ACROSS THE LESSER ANTILLES BY SUNDAY MORNING. ...HISPANIOLA... FAIR WEATHER IS PREVAILING ACROSS THE ISLAND AFTER A TROPICAL WAVE MOVED THROUGH EARLIER TODAY. MOISTURE ASSOCIATED WITH THE NEXT TROPICAL WAVE IS EXPECTED TO MOVE ACROSS THE ISLAND TO SUPPORT THE FORMATION OF SHOWERS AND TSTMS OVER THE NEXT 24-48 HOURS. ATLANTIC OCEAN... A MID-LEVEL INVERTED TROUGH ACROSS THE EASTERN GULF OF MEXICO AND THE FLORIDA PENINSULA SUPPORTS A SURFACE TROUGH WHICH AXIS REACHES THE SW N ATLC. THIS SURFACE TROUGH IS ENHANCING SCATTERED SHOWERS WEST OF 75W. THERE IS AN UPPER-LEVEL HIGH OVER SOUTH CAROLINA NEAR 34N80W. THIS FEATURE COUPLED WITH AN UPPER- LEVEL LOW NEAR 28N68W IS KEEPING A DIFFLUENT ENVIRONMENT OVER CENTRAL BAHAMAS...SUPPORTING ISOLATED CONVECTION. A SURFACE RIDGE DOMINATES ELSEWHERE ACROSS THE BASIN ANCHORED BY A 1024 MB HIGH NEAR 32N68W. FARTHER EAST...A SURFACE LOW IS NEAR 28N42W WITH SURFACE TROUGH FROM 30N38W TO 26N46W ENHANCING SCATTERED SHOWERS AND TSTMS ALONG 28N...BETWEEN 38W-54W. SEE TROPICAL WAVES SECTION FOR AREAS OF CONVECTION OVER THE SOUTHERN ATLANTIC. 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