000 AXNT20 KNHC 130549 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI AUG 13 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 08N31W TO 17N35W MOVING W AT 10-15 KT. THE WAVE LOCATION IS BETTER APPARENT IN THE MID LEVELS OF THE ATMOSPHERE...SUCH AS THE 700 MB STREAMLINE ANALYSIS. SATELLITE IMAGERY INDICATES WEAK LOW-LEVEL CYCLONIC FLOW IN THE VICINITY OF THE WAVE AXIS CONFIRMED BY SATELLITE DERIVED WINDS. DUE TO A LARGE AREA OF DRY SAHARAN AIR AND DUST TO THE EAST OF THE WAVE AXIS...CONVECTION IS MAINLY CONSTRAINED TO THE ITCZ S OF 07N. TROPICAL WAVE EXTENDS FROM 15N60W TO 23N59W MOVING W-NW AT 10-15 KT. SATELLITE IMAGERY INDICATES BROAD LOW TO MID-LEVEL CYCLONIC FLOW IN THE VICINITY OF THE WAVE AXIS WITH ELEVATED TOTAL PRECIPITABLE WATER VALUES FROM 15N-22N BETWEEN 54W-61W. ONGOING CONVECTION REMAINS LIMITED IN ORGANIZATION DUE TO AN UPPER LEVEL TROUGH AXIS TO THE NW OF THE WAVE AXIS ALONG 29N57W TO 20N67W. SCATTERED SHOWERS AND ISOLATED MODERATE CONVECTION IS FROM 16N-21N BETWEEN 56W-61W. TROPICAL WAVE EXTENDS FROM 16N73W TO 23N70W MOVING W-NW AT 10-15 KT. TOTAL PRECIPITABLE WATER IMAGERY CONTINUES TO INDICATE HIGHER VALUES OF MOISTURE AND ASSOCIATED CLOUDINESS OVER THE NORTH-CENTRAL CARIBBEAN N OF 16N BETWEEN 64W-79W THAT COINCIDES WITH THE BASE OF AN UPPER LEVEL TROUGH LOCATED NORTH OF HISPANIOLA AND PUERTO RICO NEAR 20N69W. SCATTERED SHOWERS AND ISOLATED MODERATE CONVECTION IS FROM 16N-21N BETWEEN 68W-75W. ...ITCZ... ITCZ AXIS IS ANALYZED ALONG 08N13W 05N34W 11N69W THEN RESUMING OVER NORTHERN COLOMBIA NEAR 11N75W TO 13N86W OVER NORTHERN NICARAGUA. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 180 NM OF THE AXIS BETWEEN 13W-30W...AND WITHIN 120 NM SOUTH OF THE AXIS BETWEEN 30W-45W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS EVIDENT ON WATER VAPOR IMAGERY ACROSS MUCH OF THE GULF AND SE CONUS E OF 95W. EASTERLY UPPER LEVEL FLOW DOMINATES AND A MOSTLY DRY AND SUBSIDENT AIRMASS IS COVERING THIS PORTION OF THE GULF. AT THE SURFACE...EMBEDDED UNDERNEATH THE UPPER LEVEL RIDGE ARE THE REMNANTS OF T.D. FIVE ANALYZED AS A 1008 MB LOW CENTERED NEAR 30N89W. WITH THE LOSS OF DIFFERENTIAL HEATING...CONVECTION HAS DIMINISHED THIS EVENING NEAR THE LOW CENTER AS ONLY A FEW ISOLATED SHOWERS AND TSTMS REMAIN N OF 28N BETWEEN 86W-92W. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF A SURFACE RIDGE THAT EXTENDS WESTWARD FROM THE W ATLC ALONG 24N TO THE EASTERN MEXICO COAST. A FEW ISOLATED SHOWERS ARE OCCURRING ALONG THE MEXICO COAST FROM 18N-24N W OF 95W DUE TO AN UPPER LEVEL TROUGH ALONG 100W THAT CONTINUES TO MOVE WESTWARD ACROSS INTERIOR MEXICO. CARIBBEAN SEA... UPPER LEVEL TROUGHING COVERS THE NORTH-CENTRAL CARIBBEAN SUPPORTING A WEAK SURFACE TROUGH EXTENDING FROM THE NW BAHAMAS NEAR 25N78W ACROSS CENTRAL CUBA TO NEAR 19N78W. LOW-LEVEL CONVERGENCE NEAR THE SURFACE TROUGH IS SUPPORTING WIDELY SCATTERED SHOWERS AND A FEW ISOLATED TSTMS NE OF A LINE FROM SW HAITI NEAR 18N74W TO THE YUCATAN CHANNEL NEAR 22N86W. FARTHER EAST...A TROPICAL WAVE LOCATED ACROSS CENTRAL HISPANIOLA TO 16N73W IS SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS N OF 16N BETWEEN 68W-75W. ISOLATED SHOWERS STRETCH FARTHER EAST ACROSS PUERTO RICO AND THE US/UK VIRGIN ISLANDS TO 64W. AN UPPER LEVEL DIFFLUENT ENVIRONMENT IS NOTED ON WATER VAPOR IMAGERY ACROSS THE SW CARIBBEAN AND THIS COUPLED WITH THE ITCZ AXIS ALONG 11N/12N IS GENERATING SCATTERED SHOWERS AND TSTMS...S OF 15N BETWEEN 73W-86W. ELSEWHERE...THE REMAINDER OF THE CARIBBEAN IS UNDER GENERALLY FAIR CONDITIONS...HOWEVER WITH THE TROPICAL WAVE LOCATED NE OF THE LEEWARD ISLANDS...INCREASED LOW-LEVEL MOISTURE AND A FEW ISOLATED SHOWERS AND TSTMS ARE EXPECTED TO CONTINUE OVER THE EASTERN CARIBBEAN E OF 63W THROUGH THE OVERNIGHT HOURS. AN UPPER LEVEL RIDGE AXIS EXTENDING FROM THE TROPICAL NORTH ATLC NEAR 14N56W TO THE SE CARIBBEAN NEAR 11N66W IS ENHANCING ONGOING CONVECTION OVER THE WINDWARD ISLANDS S OF 14N BETWEEN 59W-63W. ATLANTIC OCEAN... UPPER LEVEL ANTICYCLONIC FLOW DOMINATES THE W ATLC N OF 21N W OF 62W STEMMING FROM AN UPPER LEVEL HIGH CENTERED NEAR 31N81W. WHILE CONVECTIVE DEBRIS CLOUDINESS ADVECTS SOUTHWARD TO 25N...SKIES REMAIN GENERALLY UNDER FAIR CONDITIONS DUE TO SURFACE RIDGE WITH AXIS ALONG 24N/25N BETWEEN 60W TO THE STRAITS OF FLORIDA AND INTO THE GULF OF MEXICO. EMBEDDED WITHIN THIS SURFACE RIDGE...A PAIR OF WEAKNESSES ARE GENERATING AREAS OF MOISTURE AND PRECIPITATION S OF THE RIDGE AXIS. A SURFACE TROUGH EXTENDS FROM THE NW BAHAMAS NEAR 25N78W TO CENTRAL CUBA WITH NEARLY ALL SIGNIFICANT DAYTIME CONVECTIVE AREAS DIMINISHED AT THIS TIME. A FEW ISOLATED SHOWERS ARE STILL ONGOING OVER INTERIOR CUBA AND ADJACENT COASTAL WATERS BETWEEN 74W-79W. FARTHER EAST...A TROPICAL WAVE ALONG 71W CONTINUES TO ENHANCE ISOLATED SHOWERS N OF HISPANIOLA BETWEEN 66W-73W. THE BASE OF AN UPPER LEVEL TROUGH LOCATES NEAR 20N69W AND CONTINUES TO AID IN POOLING OF LOW TO MID-LEVEL MOISTURE PROVIDING LIFT FOR ISOLATED SHOWERS S OF 23N BETWEEN 63W-71W. THE UPPER LEVEL TROUGH AXIS EXTENDS FROM AN UPPER LEVEL LOW CENTERED NEAR 29N56W TO 20N69W. THIS UPPER TROUGHING SUPPORTS A WEAK SURFACE TROUGH ANALYZED FROM 25N58W TO 29N55W...ENHANCING ISOLATED SHOWERS WITHIN 120 NM EITHER SIDE OF THE AXIS. FARTHER EAST...BROAD SURFACE RIDGING DOMINATES THE EASTERN ATLC ANCHORED BY A 1032 MB SURFACE HIGH PRESSURE CENTER WELL NORTH OF THE DISCUSSION AREA. THE SURFACE RIDGE AXIS EXTENDS FROM THE AZORES TO NEAR 20N47W. SATELLITE IMAGERY TRACKING THE SAHARAN AIR LAYER INDICATES A LARGE AREA COVERING MOST OF THE EASTERN ATLC N OF 15N E OF 35W SUPPORTING OVERALL STABLE CONDITIONS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN