000 AXNT20 KNHC 170550 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN AUG 17 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 12N25W TO 20N23W MOVING W AT 5-10 KT. THE WAVE HAS MOVED WEST OF A LOW-LEVEL CYCLONIC CIRCULATION FOCUSED ON A 1012 MB LOW CENTERED ALONG THE MONSOON TROUGH NEAR 15N20W. THE WAVE COINCIDES WITH BROAD 700 MB GLOBAL MODEL INDICATED TROUGHING THAT HAS LARGELY MOVED WEST OF THE LOW AND REMAINS ASSOCIATED WITH THE WAVE AXIS BETWEEN 19W-30W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 10N-14N BETWEEN 22W- 29W...AND FROM 08N-10N BETWEEN 26W-31W. TROPICAL WAVE EXTENDS FROM 12N38W TO 18N37W MOVING W AT 5-10 KT. A 1012 MB LOW IS EMBEDDED WITHIN THE MONSOON TROUGH AT THE SOUTHERN EXTENT OF THE WAVE AXIS NEAR 12N38W. IN ADDITION...WEAK AND BROAD 700 MB TROUGHING IS NOTED ON GLOBAL MODEL DATA BETWEEN 32W-46W WITH 850 MB RELATIVE VORTICITY FOCUSED IN CLOSE PROXIMITY TO THE LOW. ISOLATED MODERATE CONVECTION IS FROM 10N- 14N BETWEEN 34W-42W. TROPICAL WAVE EXTENDS FROM 11N67W TO 21N66W MOVING W AT 15 KT. BROAD 700 MB TROUGHING ACCOMPANIES THE WAVE BETWEEN 64W-72W WITH A 850 MB RELATIVE VORTICITY MAXIMUM NOTED ALONG THE SOUTHERN EXTENT OF THE WAVE AXIS FOCUSED NEAR 13N67W. CONVECTION REMAINS LIMITED WITH THE WAVE WITH ONLY A FEW ISOLATED SHOWERS OCCURRING FROM 10N-23N BETWEEN 64W-72W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 16N17W TO 15N20W TO 12N25W TO 13N32W TO 11N38W TO 07N47W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N47W TO 08N59W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 06N-10N BETWEEN 10W-15W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER LEVEL LOW IS CENTERED NEAR 23N96W THAT INFLUENCES MUCH OF THE WESTERN GULF W OF 90W THIS EVENING. WHILE SURFACE RIDGING EXTENDS ALONG 26N/27N ACROSS THE BASIN...AMPLE DYNAMICS ASSOCIATED WITH THE UPPER LEVEL LOW IS GENERATING ISOLATED SHOWERS AND TSTMS NEAR 28N92W...AND MORE CLUSTERED ACTIVITY ALONG THE WESTERN COAST OF THE YUCATAN PENINSULA FROM 19N-21N BETWEEN 89W-93W. OTHERWISE...THE SURFACE RIDGE EXTENDING FROM THE SW NORTH ATLC AND FOCUSED ON A 1019 MB HIGH CENTERED NEAR 27N86W IN THE EAST GULF IS PROVIDING FOR OVERALL FAIR CONDITIONS AND MOSTLY CLEAR SKIES FOR THE OVERNIGHT PERIOD INTO SUNDAY. THE RIDGE AXIS IS EXPECTED TO REMAIN ANCHORED ALONG 27N THROUGH WEDNESDAY. CARIBBEAN SEA... A TROPICAL WAVE ALONG 67W IS ENTERING THE CENTRAL CARIBBEAN OVERNIGHT INTO SUNDAY BRINGING INCREASED MOISTURE AND CLOUDINESS. POSSIBLE ISOLATED SHOWERS AND TSTMS ARE OCCURRING WITHIN A NARROW CORRIDOR BETWEEN 65W-71W. OTHERWISE...THE OTHER MAJOR FEATURE IMPACTING THE BASIN IS AN UPPER LEVEL LOW CENTERED NEAR 21N83W OVER THE NW CARIBBEAN WITH AN UPPER LEVEL TROUGH AXIS EXTENDING SE THEN EAST FROM THE LOW TO 18N78W TO 19N71W. THE UPPER LEVEL LOW IS GENERATING ISOLATED SHOWERS AND TSTMS WITHIN THE ADJACENT COASTAL WATERS OF CUBA FROM 19N-22N BETWEEN 78W-81W. FINALLY...MODERATE TO FRESH TRADES ARE PERSISTING GENERALLY S OF 17N BETWEEN 67W-80W. ...HISPANIOLA... CURRENTLY...AN APPROACHING TROPICAL WAVE ALONG 67W IS RESULTING IN INCREASED MOISTURE AND CLOUDINESS FOR THE OVERNIGHT HOURS INTO SUNDAY WITH A FEW ISOLATED SHOWERS AND TSTMS EXPECTED OVERNIGHT. THE WAVE IS EXPECTED TO CONTINUE WESTWARD AND BE WEST OF THE ISLAND BY LATE SUNDAY INTO EARLY MONDAY. THEREAFTER...THE USUAL TRADE WIND FLOW WILL RESUME WITH AFTERNOON AND EVENING CONVECTION POSSIBLE. ATLANTIC OCEAN... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE SW NORTH ATLC NEAR 26N78W THAT CONTINUES TO SUPPORT SURFACE RIDGING ALONG 26N/27N. TO THE NORTH OF THE SURFACE RIDGE AXIS... GENERALLY UPPER LEVEL WESTERLY FLOW PREVAILS NEAR THE BASE OF AN UPPER LEVEL TROUGH OVER THE WESTERN NORTH ATLC. INCREASE MOISTURE AND CLOUDINESS IS NOTED ON SATELLITE IMAGERY THIS EVENING WITH ISOLATED SHOWERS OCCURRING N OF 28N W OF 62W. OTHERWISE...THE SURFACE RIDGE IS PROVIDING MOSTLY FAIR CONDITIONS FOR THE BAHAMAS AND FLORIDA STRAITS. FARTHER EAST... THE RIDGING IS ANCHORED BY A 1023 MB HIGH CENTERED NEAR 27N60W AND A 1022 MB HIGH CENTERED NEAR 34N54W. ACROSS THE CENTRAL ATLC...WHILE AN UPPER LEVEL RIDGE REMAINS ANCHORED 29N46W...AT THE SURFACE...A COLD FRONT ENTERS THE DISCUSSION AREA NEAR 32N35W AND EXTENDS SW TO 27N42W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM EITHER SIDE OF THE FRONT. FINALLY...ANOTHER SURFACE RIDGE EXTENDS ACROSS THE EASTERN ATLC STEMMING FROM A 1026 MB HIGH CENTERED WELL NORTH OF THE AREA NEAR 45N15W. THE RIDGE AXIS EXTENDS S-SW TO 32N24W TO 25N34W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN