000 AXNT20 KNHC 151753 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN AUG 15 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 10N18W TO 16N20W TO 22N19W MOVING W AT 15-20 KT. THE WAVE LIES ON THE LEADING EDGE OF MAXIMUM TOTAL PRECIPITABLE WATER VALUES BEGINNING TO EMERGE OFF OF THE W AFRICA COAST AND ALSO IS EMBEDDED WITHIN A BROAD LOW-LEVEL CYCLONIC GYRE S OF 22N BETWEEN 15W-35W. A 1011 MB LOW IS LOCATED WEST OF THE WAVE CENTERED NEAR 17N22W THAT IS FORECAST TO DRIFT SW OVER THE NEXT 24 HOURS. WHILE THE WAVE COINCIDES WITH A 600-700 MB TROUGH AXIS...IT REMAINS SHROUDED IN THE SAHARAN AIR LAYER AND THEREFORE CONVECTION IS CONFINED TO THE AREA NEAR THE ITCZ AXIS. SCATTERED MODERATE CONVECTION IS FROM 07N-14N BETWEEN 14W-22W. TROPICAL WAVE EXTENDS FROM 08N51W TO 13N56W TO 19N58W MOVING W AT 15-20 KT. THE WAVE REMAINS EMBEDDED WITHIN A WEAK CYCLONIC LOW-LEVEL PERTURBATION THAT ALSO FOLLOWS ON THE LEADING EDGE OF AN EXTENSIVE SAHARAN AIR LAYER THAT STRETCHES EASTWARD FROM THE WAVE AXIS TO 30W. SCATTERED MODERATE CONVECTION IS APPROACHING THE LESSER ANTILLES AND IS LOCATED FROM 11N-18N BETWEEN 58W-60W. AN AREA OF ISOLATED MODERATE CONVECTION IS LOCATED EAST OF THE WAVE FROM 13N-17N BETWEEN 51W-56W. TROPICAL WAVE IS ALONG 76W S OF 18N MOVING W AT 15-20 KT. GLOBAL MODEL GUIDANCE INDICATES WEAK LOW-LEVEL CYCLONIC CURVATURE IN THE VICINITY OF THE WAVE AXIS AND IS OBSERVED ON LATEST VISIBLE SATELLITE IMAGERY. DEEP TROPICAL MOISTURE IS NOTED ON TOTAL PRECIPITABLE WATER IMAGERY WEST OF THE WAVE AXIS THAT CONTINUES TO AID IN GENERATING SCATTERED MODERATE AND ISOLATED STRONG CONVECTION FROM 14N-18N BETWEEN 70W-84W. TROPICAL WAVE IS ALONG 95W S OF 21N MOVING W AT 10-15 KT. THE WAVE EXTENDS INTO THE E PACIFIC REGION THROUGH THE ISTHMUS OF TEHUANTEPEC GENERATING SCATTERED MODERATE AND ISOLATED STRONG CONVECTION S OF 17N OVER SOUTHERN MEXICO. ...ITCZ... ITCZ AXIS IS ANALYZED ALONG 11N19W 08N32W 09N48W 07N53W 10N74W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 05N-11N BETWEEN 20W-40W. SIMILAR CONVECTION IS FROM 07N-10N BETWEEN 55W-59W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONE COVERS MUCH OF THE GULF E OF 96W THAT REMAINS CENTERED OVER LOUISIANA. OVERALL...THIS UPPER LEVEL RIDGE IS SUPPORTING A SURFACE RIDGE ORIENTED SE TO NW FROM CUBA TO THE TEXAS/LOUISIANA BORDER NEAR 30N94W AND IS ANCHORED BY A 1016 MB HIGH CENTERED IN THE E GULF NEAR 26N86W. LIGHT E-SE WINDS ARE LOCATED SW OF THE RIDGE AXIS WITH GENERALLY FAIR SKIES NOTED ON VISIBLE SATELLITE IMAGERY THIS AFTERNOON S OF 27N AND W OF 93W. HOWEVER...OVER THE NE GULF...A SURFACE TROUGH EXTENDS FROM A 1013 MB LOW CENTERED OVER SE ALABAMA TO PANAMA CITY FLORIDA AND INTO THE NORTH-CENTRAL GULF NEAR 29N90W. MOSAIC DOPPLER RADAR AND LIGHTNING DATA INDICATE NUMEROUS SHOWERS AND SCATTERED TSTMS N OF 27N BETWEEN 84W-92W. THE SURFACE LOW IS FORECAST TO MOVE SW AND EMERGE OUT INTO THE FAR NORTH-CENTRAL GULF WATERS OVER THE NEXT 12-24 HOURS ON THE NORTHEASTERLY UPPER LEVEL STEERING FLOW ASSOCIATED WITH THE UPPER LEVEL ANTICYCLONE CENTERED OVER LOUISIANA. SW TO W WINDS INCREASING TO 20 KT BY MONDAY AFTERNOON OVER THE MIDDLE GULF. CARIBBEAN SEA... THE CARIBBEAN NW OF A LINE FROM HISPANIOLA TO PANAMA IS UNDER THE INFLUENCE OF UPPER LEVEL NE FLOW ON THE SOUTHERN PERIPHERY OF A LARGE ANTICYCLONIC CENTERED OVER THE SE CONUS. UPPER LEVEL MOISTURE AND CLOUDINESS CONTINUES TO ADVECT SW FROM THE BAHAMAS...ACROSS CUBA...AND THE NW CARIBBEAN. LOW-LEVEL CONVERGENCE OF THE EASTERLY TRADES AND ATMOSPHERIC INSTABILITY ARE GENERATING SCATTERED SHOWERS AND TSTMS OVER THE CARIBBEAN N OF 13N W OF 74W. A TROPICAL WAVE ALONG 76W IS ALSO PROVIDING LOW-LEVEL FOCUS FOR THIS CONVECTIVE ACTIVITY AS IT MOVES WESTWARD. ELSEWHERE...AN UPPER LEVEL TROUGH EXTENDS FROM THE SW NORTH ATLC NEAR 21N67W TO AN UPPER LEVEL LOW CENTERED NEAR 14N73W THAT IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS N OF 14N BETWEEN 65W-74W. THIS INCLUDES PUERTO RICO...THE MONA PASSAGE...AND HISPANIOLA. WITH THE APPROACH OF THE TROPICAL WAVE ALONG 57W...THE LESSER ANTILLES ARE FORECAST TO SEE AN INCREASE IN LOW-LEVEL MOISTURE...SCATTERED SHOWERS...AND ISOLATED TSTMS OVER THE NEXT 24-36 HOURS. ATLANTIC OCEAN... THE UPPER LEVEL ANTICYCLONE LOCATED OVER THE SE CONUS EXTENDS EASTWARD TO 70W PROVIDING MUCH OF THE W ATLC WITH NE UPPER LEVEL FLOW. TO THE EAST...AN UPPER LEVEL TROUGH AXIS EXTENDS ALONG 32N63W TO 27N68W AND SUPPORTS A STATIONARY FRONT ANALYZED ALONG 32N59W 27N70W 30N78W TO THE GEORGIA COAST NEAR 31N81W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 150 NM SE OF THE FRONT E OF 70W...FROM 19N-27N BETWEEN 70W-77W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING SOUTH OF THE FRONT WHERE HIGHER INSTABILITY IS LOCATED FROM 22N-32N BETWEEN 77W-81W. FARTHER EAST...THE REMAINDER OF THE ATLC IS UNDER GENERALLY FAIR CONDITIONS DUE TO A SURFACE RIDGE ANCHORED BY A 1029 MB HIGH CENTERED OVER THE AZORES NEAR 39N28W. THE SURFACE RIDGE AXIS EXTENDS FROM THE HIGH SW ALONG 32N40W TO ANGUILLA NEAR 19N63W. VISIBLE SATELLITE IMAGERY ALSO INDICATES A LARGE AREA OF SAHARAN DUST THAT COVERS THE EASTERN ATLC FROM 12N-33N BETWEEN 35W-52W...AND FROM 10N-25N E OF 35W TO THE W AFRICA COAST. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN