000 AXNT20 KNHC 211755 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT JUN 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 06N26W TO 15N25W MOVING W AT 20-25 KT. SATELLITE IMAGERY SHOWS A BROAD LOW-LEVEL CYCLONIC CIRCULATION ABOUT THE WAVE AXIS THAT COINCIDES WITH GLOBAL MODEL INDICATED 700 MB TROUGHING AND 850 MB RELATIVELY VORTICITY FIELDS. THE WAVE IS FORECAST TO REACH THE EASTERN TROPICAL ATLC OFFSHORE ZONES BY EARLY TUESDAY IMPACTING THE LESSER ANTILLES TUESDAY INTO WEDNESDAY OF NEXT WEEK. POSSIBLE ISOLATED MODERATE CONVECTION IS FROM 05N-11N BETWEEN 23W-29W. TROPICAL WAVE EXTENDS FROM 05N33W TO 09N32W MOVING W AT 10 KT. THE WAVE REMAINS LOW AMPLITUDE AND EMBEDDED WITHIN THE ITCZ AXIS. GIVEN ITS WEAK NATURE AND SLOWER MOVEMENT...THE TROPICAL WAVE TO THE EAST ALONG 26W WILL LIKELY ABSORB ANY ENERGY ASSOCIATED WITH THIS WAVE DURING THE NEXT 24 HOURS. ISOLATED MODERATE CONVECTION IS FROM 04N-08N BETWEEN 31W-34W. TROPICAL WAVE EXTENDS FROM 09N75W TO 18N73W MOVING W AT 15 KT. THE WAVE CONTINUES TO MOVE BENEATH SOUTHWESTERLY FLOW ALOFT ASSOCIATED WITH AN UPPER LEVEL TROUGH ALONG 85W WITH STRONG DEEP LAYER ENVIRONMENTAL WIND SHEAR HINDERING ANY SIGNIFICANT CONVECTION AND ANY FURTHER DEVELOPMENT OF THIS WAVE ACROSS THE CARIBBEAN SEA. POSSIBLE ISOLATED MODERATE CONVECTION IS FROM 10N- 18N BETWEEN 72W-78W. TROPICAL WAVE EXTENDS FROM 14N95W TO 19N94W MOVING W AT 10 KT. THE WAVE IS QUICKLY LOSING ANY DISCERNIBLE LOW-LEVEL SIGNATURE AS IT MOVES ACROSS THE HIGHER TERRAIN OF MEXICO AND BECOMES EMBEDDED WITHIN A MOIST AIRMASS ACROSS THE EAST PACIFIC AND MEXICO BETWEEN 95W-110W. ISOLATED MODERATE CONVECTION IS FROM 16N-20N BETWEEN 95W-97W.. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 16N17W TO 07N25W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N25W TO 06N33W TO 05N40W TO 02N44W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 05N-07N BETWEEN 33W-42W. ...DISCUSSION... GULF OF MEXICO... NORTHERLY UPPER LEVEL FLOW INFLUENCES THE GULF BETWEEN A MIDDLE TO UPPER LEVEL LOW CENTERED OVER WESTERN CUBA NEAR 23N83W AND AN AMPLIFIED MIDDLE TO UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED OVER SOUTHERN MEXICO NEAR 17N100W WITH AXIS EXTENDING NORTHWARD ALONG 100W TO OVER TEXAS AND LOUISIANA. OVERALL THE RIDGING IS PROVIDING DRY AIR AND SUBSIDENCE TO MUCH OF THE GULF THIS AFTERNOON FURTHER SUPPORTING SURFACE RIDGING EXTENDING ACROSS THE CENTRAL GULF WATERS AND THE MID-MISSISSIPPI RIVER VALLEY TO THE NORTH...AND ACROSS EASTERN MEXICO TO THE WEST. THE ONLY AREA OF SIGNIFICANT WEATHER OCCURRING AT THIS TIME IS A FEW ISOLATED SHOWERS AND TSTMS ASSOCIATED WITH AN AREA OF LOWER PRESSURE NOTED ACROSS NORTHERN FLORIDA AND THE ADJACENT SW NORTH ATLC WATERS. THIS ACTIVITY IS FROM 28N-29N BETWEEN 82W-86W. OTHERWISE...GENTLE TO MODERATE WINDS ARE EXPECTED THROUGH EVENING AND OVERNIGHT HOURS INTO SUNDAY AS THE SURFACE RIDGE REMAINS ANCHORED ACROSS THE CENTRAL AND EASTERN GULF WATERS. CARIBBEAN SEA... A MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER WESTERN CUBA NEAR 23N83W THAT EXTENDS A TROUGH AXIS ALONG 85W TO A BROAD BASE OVER COSTA RICA. MOISTURE CONTINUES TO ADVECT NORTHWARD ON THE EASTERN PERIPHERY OF THIS TROUGHING AMIDST A TROPICAL WAVE PROGRESSING WESTWARD ACROSS THE WESTERN CARIBBEAN. GIVEN THE AMPLE MIDDLE TO UPPER LEVEL DYNAMICS...ISOLATED SHOWERS AND TSTMS ARE OCCURRING FROM 09N-21N BETWEEN 72W-85W. WHILE THE TROPICAL WAVE IS MOVING THROUGH A DIFFLUENT ENVIRONMENT W OF 72W...ENVIRONMENTAL WIND SHEAR IS PREVENTING ANY SIGNIFICANT DEVELOPMENT. THE REMAINDER OF THE EASTERN CARIBBEAN IS UNDER MOSTLY CLEAR SKIES WITH ONLY A FEW ISOLATED SHOWERS AND TSTMS OCCURRING N OF 16N BETWEEN 62W-67W. TRADES ARE EXPECTED TO PERSIST DURING THE NEXT 24 TO 36 HOURS IN THE RANGE OF 15 TO 25 KT. ...HISPANIOLA... AN UPPER LEVEL RIDGE IS NOTED ON WATER VAPOR IMAGERY OVER THE ISLAND THIS AFTERNOON...HOWEVER MOISTURE ADVECTING NORTH- NORTHEASTWARD ON THE EASTERN PERIPHERY OF AN UPPER LEVEL TROUGH TO THE WEST ALONG 85W IS PROVIDING INCREASED CLOUDINESS AND ISOLATED SHOWERS FOR HISPANIOLA. WITH PEAK DAYTIME HEATING AND INSTABILITY...GIVEN THE OVERALL DIFFLUENT ENVIRONMENT ALOFT... CONVECTION IS EXPECTED TO INCREASE THIS AFTERNOON AND EVENING ACROSS THE ISLAND...THEN GRADUALLY DIMINISH THROUGH THE OVERNIGHT HOURS. ATLANTIC OCEAN... AN UPPER LEVEL LOW IS CENTERED 29N74W THAT EXTENDS UPPER LEVEL TROUGHING SW TO ANOTHER UPPER LEVEL LOW CENTERED OVER WESTERN CUBA NEAR 23N83W. THIS AREA OF UPPER LEVEL TROUGHING SUPPORTS A WEAK 1014 MB LOW CENTERED NEAR 30N79W WITH A SURFACE TROUGH EXTENDING S-SW TO THE FLORIDA PENINSULA NEAR 27N80W. WIDELY SCATTERED SHOWERS AND TSTMS ARE OCCURRING FROM 25N-30N BETWEEN 76W-79W...WITH ISOLATED SHOWERS AND TSTMS OCCURRING ELSEWHERE FROM 20N-26N BETWEEN 69W-78W. OTHERWISE...SURFACE RIDGING EXTENDS FROM THE CENTRAL ATLC ALONG 24N TO THE FLORIDA STRAITS AND INTO THE GULF OF MEXICO PROVIDING GENERALLY FAIR WEATHER CONDITIONS THIS AFTERNOON. A FEW ISOLATED SHOWERS AND TSTMS ARE HOWEVER OCCURRING NORTH OF PUERTO RICO FROM 18N-23N BETWEEN 63W- 69W DUE MOSTLY TO AN UPPER LEVEL DIFFLUENT ENVIRONMENT. FINALLY...THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1023 MB HIGH CENTERED NEAR 28N32W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN