000 AXNT20 KNHC 171749 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI MAY 17 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 02N50W TO 09N46W MOVING W AT 15 KT. THE WAVE REMAINS LOW-AMPLITUDE AND ON THE WESTERN EXTENT OF THE ITCZ AXIS COINCIDING WITH A GLOBAL MODEL INDICATED AREA OF MAXIMUM POTENTIAL VORTICITY AT 315K. TOTAL PRECIPITATABLE WATER AND SATELLITE IMAGERY ALSO INDICATE A MAXIMUM IN LOW-LEVEL MOISTURE CONVERGENCE AND CLOUDINESS IN THE VICINITY OF THE WAVE AXIS. ISOLATED MODERATE CONVECTION IS FROM 04N-10N BETWEEN 45W- 57W. THE WAVE IS EXPECTED TO CONTINUE MOVING WESTWARD WITH PRECIPITATION PROBABILITIES INCREASING OVER THE WEEKEND ACROSS THE WINDWARD ISLANDS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 10N15W TO 06N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 06N20W TO 03N28W TO 01N34W TO 03N47W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 01N-05N BETWEEN THE PRIME MERIDIAN AND 09W... AND FROM 01N-05N BETWEEN 27W-39W. SCATTERED MODERATE CONVECTION IS FROM 03N-07N BETWEEN 14W-25W. ...DISCUSSION... GULF OF MEXICO... AT FIRST GLANCE ON VISIBLE SATELLITE IMAGERY THE GULF BASIN REMAINS UNDER FAIRLY TRANQUIL CONDITIONS THIS AFTERNOON. WATER VAPOR IMAGERY INDICATES UPPER LEVEL WESTERLY FLOW WITH MID-LEVEL RIDGING PROVIDING FOR OVERALL STABLE CONDITIONS. AT THE SURFACE...A RIDGE AXIS EXTENDS FROM THE SW NORTH ATLC REGION NEAR 29N80W TO 26N95W AND IS PROVIDING SE WINDS GENERALLY IN THE RANGE OF 5 TO 10 KT EAST OF 90W AND 10 TO 20 KT WEST OF 90W. THE RIDGING IS EXPECTED TO REMAIN NEARLY STATIONARY OVER THE WEEKEND INTO EARLY NEXT WEEK WITH LITTLE CHANGE REGARDING WIND SPEEDS AND DIRECTION AS NOTED ABOVE. FINALLY...OF NOTE...VISIBLE SATELLITE IMAGERY INDICATES MODERATELY DENSE SMOKE MOVING NORTH- NORTHWESTWARD OFF THE SOUTHERN MEXICO COAST THAT COVERS A PORTION OF THE SW GULF S OF 22N BETWEEN 92W-97W. THE SMOKE IS DUE TO SEVERAL AGRICULTURAL FIRES ACROSS SOUTHERN MEXICO AND NORTHERN CENTRAL AMERICA. CARIBBEAN SEA... DRY AND STABLE WESTERLY MIDDLE TO UPPER LEVEL FLOW IS NOTED ON WATER VAPOR IMAGERY ACROSS THE NW CARIBBEAN WITH UPPER LEVEL WINDS SHIFTING SLIGHTLY MORE WEST-SOUTHWEST OVER THE CENTRAL AND EASTERN CARIBBEAN E OF 72W. MODERATELY DRY AIR PREVAILS ALOFT E OF 72W...HOWEVER VISIBLE SATELLITE IMAGERY SHOWS A FEW PASSING CIRRUS CLOUDS AND POSSIBLE CONVECTIVE DEBRIS CLOUDINESS FROM CONVECTION OCCURRING OVER THE SW CARIBBEAN. SCATTERED SHOWERS AND TSTMS ARE OCCURRING S OF 12N BETWEEN 76W-84W AND LIKELY WILL PERSIST DUE TO LOW-LEVEL MOISTURE CONVERGENCE AND THE CLOSE PROXIMITY OF THE MONSOON TROUGH AXIS ALONG 09N/10N. OTHERWISE... TRADES CONTINUE IN THE RANGE OF 10 TO 20 KT WITH SLIGHTLY HIGHER WIND SPEEDS EXPECTED WITHIN 150 NM OF THE COAST OF COLOMBIA. A FEW AREAS OF ISOLATED SHOWERS ARE OCCURRING IN THE VICINITY OF JAMAICA AND THE ADJACENT COASTAL WATERS FROM 16N-20N BETWEEN 75W- 82W...HOWEVER THE OVERALL TRANQUIL WEATHER PATTERN IS EXPECTED TO REMAIN IN PLACE THROUGH THE WEEKEND. HISPANIOLA... CURRENTLY NORTHWEST WINDS ALOFT ARE CONTINUING TO PROVIDE AN OVERALL STABLE ENVIRONMENT OVER THE ISLAND THIS AFTERNOON. DRYING ALOFT HAS TAKEN HOLD DURING THE LAST 24 TO 36 HOURS AND MOST LOW-LEVEL MOISTURE AND ISOLATED SHOWERS RIDING TRADE WIND FLOW ARE NOW LOCATED ACROSS THE ADJACENT SOUTHERN COASTAL WATERS AND WELL WEST OF THE AREA IN THE VICINITY OF JAMAICA. WHILE THE TRADE WIND FLOW REGIME WILL REMAIN PERSISTENT THROUGH THE WEEKEND...AND GIVEN THE DRIER UPPER LEVEL FLOW PATTERN IN PLACE...THE MOST LIKELY PRECIPITATION WILL BE ISOLATED SHOWERS AND TSTMS DURING THE AFTERNOON AND EARLY EVENING HOURS ACROSS THE ISLAND WHEN PEAK DAYTIME HEAT AND INSTABILITY OCCUR. ANY AREAS THAT RECEIVE MEASUREABLE AMOUNTS OF RAINFALL WILL LIKELY BE PRONE TO LOCALIZED FLOODING. ATLANTIC OCEAN... WEST-NORTHWESTERLY FLOW ALOFT IS NOTED ON WATER VAPOR IMAGERY OVER MUCH OF THE SW NORTH ATLC AS AN UPPER LEVEL TROUGH AXIS CONTINUES TO MOVE INTO THE CENTRAL ATLC. THIS RATHER STABLE REGIME ALOFT IS SUPPORTIVE OF A SURFACE RIDGE ANCHORED BY A 1024 MB HIGH CENTERED SOUTH OF BERMUDA NEAR 31N65W AND IS PROVIDING FOR OVERALL FAIR CONDITIONS. ON THE SOUTHERN AND WESTERN PERIPHERY OF THE RIDGE HOWEVER...A FEW ISOLATED SHOWERS AND TSTMS ARE POSSIBLE AS NOTED ON SATELLITE IMAGERY AND MOSAIC DOPPLER RADAR IMAGERY OFF THE COAST OF THE FLORIDA PENINSULA. FARTHER EAST...THE PREVIOUSLY MENTIONED UPPER LEVEL TROUGH AXIS EXTENDS FROM 30N47W SW TO 18N66W AND MARGINALLY SUPPORTS A GRADUALLY WEAKENING STATIONARY ANALYZED FROM 32N56W TO 21N69W. ISOLATED SHOWERS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THE BOUNDARY N OF 23N. IN ADDITION ACROSS THE CENTRAL ATLC...A WEAK 1021 MB LOW IS CENTERED NEAR 29N47W WITH AN ASSOCIATED SURFACE TROUGH FROM 27N43W TO 32N49W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 150 NM OF THE LOW CENTER...AND EAST OF THE LOW CENTER FROM 26N-32N BETWEEN 40W-45W. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1033 MB HIGH CENTERED NW OF THE AZORES NEAR 43N33W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN