000 AXNT20 KNHC 230549 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN JUN 23 2013 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 02N41W TO 10N38W MOVING W AT 20 KT. THE WAVE COINCIDES WITH A 700 MB TROUGH ALONG 42W AND A RELATIVE MAXIMUM IN DEEP LAYER MOISTURE NOTED ON TOTAL PRECIPITABLE WATER IMAGERY FROM 04N-11N BETWEEN 35W-42W. ALSO OF NOTE...THE WAVE IS LOCATED WITHIN AN AREA OF CLEARING EMBEDDED IN THE SAHARAN AIR LAYER SURROUNDING THE WAVE AXIS. WIDELY SCATTERED MODERATE CONVECTION IS FROM 04N-10N BETWEEN 35W-44W. TROPICAL WAVE EXTENDS FROM 01N52W TO 12N52W MOVING W AT 15 KT. THE WAVE LIES WITHIN A RELATIVE MAXIMUM ON TOTAL PRECIPITABLE WATER IMAGERY FROM 04N-12N BETWEEN 50W-57W. THE SAHARAN AIR LAYER AS NOTED ON GOES-R PG IMAGERY REMAINS A STRONG SIGNAL AND CONTINUES TO SURPRESS ANY SIGNIFICANT DEEP CONVECTION IN THE VICINITY OF THE WAVE...HOWEVER ISOLATED MODERATE CONVECTION IS FROM 08N-10N BETWEEN 53W-56W. TROPICAL WAVE EXTENDS FROM 11N85W TO 20N84W MOVING W AT 15 KT. THE WAVE LIES WITHIN ZONAL EASTERLY FLOW AT 700 MB AND IS BECOMING MORE DIFFICULT TO TRACK. WITH SOME OF THE ENERGY FRACTURING SATURDAY...NOW LOCATED OFFSHORE OF THE FLORIDA PENINSULA IN THE SW NORTH ATLC WATERS...THE REMAINING ENERGY IS MOVING BENEATH UNFAVORABLE UPPER LEVEL WINDS AS NORTH- NORTHWESTERLY FLOW ALOFT EXTENDS FROM THE NW GULF OF MEXICO THROUGH TO THE EQUATOR OVER THE EASTERN PACIFIC WATERS. AS A RESULT...CONVECTION REMAINS LIMITED OVERALL WITH ONLY WIDELY SCATTERED MODERATE FROM 07N-12N BETWEEN 76W-84W...WHICH COINCIDES WITH CLOSE PROXIMITY TO THE MONSOON TROUGH AXIS ALONG 10N. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 12N16W TO 10N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 10N20W TO 08N26W TO 08N39W TO 06N46W TO 08N53W TO 06N58W. ISOLATED MODERATE CONVECTION IS FROM 04N-06N BETWEEN 26W-31W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES AN MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER THE SE CONUS NEAR 36N84W THAT SUPPORTS WEAK SURFACE TROUGHING EXTENDING FROM THE SW NORTH ATLC OFFSHORE OF GEORGIA WEST-SOUTHWEST ACROSS NORTHERN FLORIDA. THE SURFACE TROUGH EXTENDS FROM NEAR JACKSONVILLE FLORIDA TO NEAR 28N90W PROVIDING FOCUS FOR ISOLATED SHOWERS N OF 26N E OF 90W. OTHERWISE...THE REMAINDER OF THE BASIN IS UNDER THE INFLUENCE OF WEAK SURFACE RIDGING ANCHORED BY A WEAK 1016 MB HIGH CENTERED OFFSHORE OF EAST-CENTRAL MEXICO NEAR 21N97W. ASIDE FROM ANY SMALL VARIATION IN WIND DIRECTION ASSOCIATED WITH THE SURFACE TROUGHING OVER THE NE GULF...SYNOPTICALLY EAST-SOUTHEAST WINDS IN THE RANGE OF 10 TO 15 KT ARE EXPECTED OVERNIGHT THROUGH EARLY MONDAY. THE RIDGING SHOULD MAINTAIN ITSELF SUNDAY AND THROUGHOUT MUCH OF THE WEEK AHEAD. CARIBBEAN SEA... THE CARIBBEAN IS LARGELY INFLUENCE BY A MIDDLE TO UPPER LEVEL LOW CENTERED NORTH OF EASTERN CUBA NEAR 21N75W. THE ASSOCIATED TROUGH AXIS DIPS WEST-SOUTHWEST TO 17N84W. WATER VAPOR IMAGERY INDICATES THE AREA WITHIN THE TROUGH ARE RELATIVELY DRY AND STABLE ALOFT WHICH IS PROVIDING FOR OVERALL TRANQUIL CONDITIONS N OF 15N BETWEEN 73W-88W. A FEW ISOLATED SHOWERS AND TSTMS ARE HOWEVER OCCURRING IN THE VICINITY OF WESTERN CUBA...INCLUDING THE ADJACENT COASTAL WATERS N OF 21N BETWEEN 80W-84W. OTHERWISE ON THE SOUTHWEST PERIPHERY OF THE TROUGH...NORTH-NORTHWESTERLY FLOW ALOFT DOMINATES AND IS PROVIDING FOR SUFFICIENT UPPER LEVEL DIFFLUENCE TO SUPPORT WIDELY SCATTERED SHOWERS AND TSTMS S OF 15N W OF 77W...INCLUDING INLAND PORTIONS OF CENTRAL AMERICA. EAST OF THE UPPER LEVEL TROUGH AXIS...SOUTHWESTERLY FLOW ALOFT CONTINUES TO ADVECT MOISTURE FROM OVER NORTHERN SOUTH AMERICA TOWARDS THE MONA PASSAGE AND PUERTO RICO. MOST OF THIS MOISTURE REMAINS AS INCREASED CLOUD COVER ACROSS THE EASTERN CARIBBEAN... HOWEVER A FEW ISOLATED LOW-TOPPED SHOWERS ARE NOTED ON SATELLITE IMAGERY N OF 13N BETWEEN 64W-75W...THAT STRETCH NORTHEASTWARD INTO THE ADJACENT WATERS OF THE SW NORTH ATLC. HISPANIOLA... CURRENTLY CONDITIONS REMAIN RELATIVELY TRANQUIL THIS EVENING ACROSS THE ISLAND...HOWEVER A FEW ISOLATED LIGHT SHOWERS ARE NOTED ON SATELLITE IMAGERY. WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL LOW IS CENTERED NORTHWEST OF THE ISLAND NEAR 21N75W WITH PRIMARILY MOIST SOUTHWESTERLY FLOW ALOFT LOCATED EAST OF THE ISLAND OVER PUERTO RICO...THE MONA PASSAGE...AND FAR EASTERN DOMINICAN REPUBLIC. GLOBAL MODEL DATA INDICATES THE LOW WILL WEAKEN OVER THE NEXT FEW DAYS AND LIFT GRADUALLY NORTHWARD WITH SOUTHWESTERLY FLOW ALOFT BECOMING DOMINANT THROUGH EARLY NEXT WEEK. AS A RESULT...THE ATMOSPHERE WILL FAVOR BECOMING MORE UNSTABLE DURING THE AFTERNOON AND EVENING HOURS WITH SCATTERED SHOWERS AND TSTMS EXPECTED DUE TO PEAK DAYTIME HEATING AND INSTABILITY. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LOW CENTERED OVER THE SE CONUS NEAR 36N84W SUPPORTS WEAK SURFACE TROUGHING INLAND ACROSS THE CAROLINAS AND GEORGIA THIS EVENING. A SURFACE TROUGH...ANALYZED FROM 26N79W TO 31N77W CONTINUES TO MOVE NW TOWARDS THE FLORIDA PENINSULA AND SE CONUS COAST. ISOLATED SHOWERS AND TSTMS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE SURFACE TROUGH. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1034 MB HIGH CENTERED NORTH OF THE AZORES NEAR 40N29W AND A 1027 MB HIGH CENTERED IN THE VICINITY OF BERMUDA NEAR 33N66W. A STABLE DRY AIRMASS COVERS MUCH OF THE EASTERN ATLC INDICATED BY A LARGE AREA OF SUSPENSED SAHARAN DUST THAT EXTENDS FROM THE COAST OF AFRICA TO 55W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN