000 AXNT20 KNHC 130542 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT SUN OCT 13 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 13N68W TO 21N67W MOVING W AT 15-20 KT. THE WAVE LIES BENEATH RELATIVELY DRY AIR ALOFT WITHIN WEAK ANTICYCLONIC FLOW WITH VERY LITTLE CONVECTION NOTED ON SATELLITE IMAGERY AT THIS TIME. WATER VAPOR IMAGERY ALSO INDICATES AS THE WAVE CONTINUES WEST THAT IT WILL LIE BENEATH INCREASED SOUTH- SOUTHWESTERLY UPPER LEVEL DIFFLUENT FLOW...HOWEVER UNDER INCREASING WIND SHEAR AS WELL. ANY SIGNIFICANT DEEP CONVECTION IS LACKING THIS EVENING AS MOST OF THE OVERALL CONVECTIVE ACTIVITY IS FOUND ACROSS THE CENTRAL CARIBBEAN SEA AND PORTIONS OF THE SW NORTH ATLC IN ASSOCIATION WITH AN UPPER LEVEL LOW CENTERED NEAR 17N80W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 14N17W TO 08N31W TO A 1010 MB LOW CENTERED NEAR 12N44W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 12N44W TO 10N61W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 04N-10N BETWEEN 11W-16W. SCATTERED MODERATE CONVECTION IS FROM 10N-14N BETWEEN 23W-33W...FROM 09N-15N BETWEEN 39W-47W...AND FROM 11N-13N BETWEEN 48W-56W. ...DISCUSSION... GULF OF MEXICO... A MIDDLE TO UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER NE MEXICO NEAR 23N99W THAT IS PROVIDING THE GULF BASIN WITH NORTHWEST TO NORTHERLY FLOW ALOFT THIS EVENING. WATER VAPOR IMAGERY INDICATES THE FLOW IS MOSTLY DRY AIR AND VERY STABLE RESULTING IN MOSTLY CLEAR SKIES AND FAIR CONDITIONS AT THE SURFACE. A 1019 MB HIGH CENTERED IN THE NE GULF WATERS NEAR 29N87W FURTHER PROMOTES THE FAIR CONDITIONS WITH ONLY A FEW ISOLATED SHOWERS AND TSTMS OCCURRING ALONG THE GULF COAST FROM 28N-31N BETWEEN 89W-94W. SURFACE RIDGING IS EXPECTED TO REMAIN ACROSS THE GULF THROUGH LATE WEDNESDAY WHEN THE NEXT FRONTAL BOUNDARY IS FORECAST TO EMERGE OFF THE TEXAS GULF COAST. CARIBBEAN SEA... AN UPPER LEVEL LOW IS CENTERED NEAR 17N80W AND EXTENDS A TROUGH AXIS SW TO NEAR 10N84W. WEST OF THE TROUGH AXIS...WATER VAPOR IMAGERY INDICATES VERY DRY AND STABLE AIR WITHIN NORTH- NORTHEASTERLY FLOW PROVIDING FOR RELATIVELY QUIET CONDITIONS THIS EVENING N OF 16N W OF 81W. HOWEVER THE REMAINDER OF THE CENTRAL AND SW CARIBBEAN COMES UNDER THE INFLUENCE OF THE UPPER LEVEL LOW AND THE ASSOCIATED LIFTING DYNAMICS WHICH CONTINUE TO GENERATE SCATTERED SHOWERS AND ISOLATED TSTMS BETWEEN 70W-80W AND S OF 15N BETWEEN 80W-84W. FARTHER EAST...A WEAK TROPICAL WAVE IS ANALYZED ALONG 68W IMPACTING THE EASTERN CARIBBEAN WITH ISOLATED SHOWERS ACROSS THE LESSER ANTILLES BETWEEN 58W-64W AND IN THE VICINITY OF THE WAVE WITHIN 120 NM EITHER SIDE OF THE AXIS. HISPANIOLA... CURRENTLY THE ISLAND FALLS WITHIN AN AREA OF MIDDLE TO UPPER LEVEL DIFFLUENCE NOTED TO THE EAST OF AN UPPER LEVEL LOW CENTERED NEAR 17N80W. THE ADVECTION OF MOISTURE FROM THE EAST PACIFIC NEAR THE BASE OF THE TROUGHING AND MOISTURE FROM NORTHERN SOUTH AMERICA NORTHWARD ACROSS THE CENTRAL CARIBBEAN SEA AND SW NORTH ATLC IS PROVIDING FOR ISOLATED SHOWERS AND TSTMS THIS EVENING. AS THE UPPER LEVEL LOW IS FORECAST TO EVENTUALLY DRIFT SOUTHWEST BY LATE SUNDAY INTO MONDAY...UNTIL THEN HISPANIOLA WILL LIKELY REMAIN IN AN UPPER LEVEL DIFFLUENT PATTERN WITH INCREASED PROBABILITY OF ISOLATED SHOWERS AND TSTMS. OF COURSE AS ALWAYS WITH PEAK DAYTIME HEATING AND INSTABILITY...MAXIMUM AREAL COVERAGE OF CONVECTION IS LIKELY TO OCCUR IN THE AFTERNOON AND EVENING HOURS. THE ADDITION OF A TROPICAL WAVE CURRENTLY ALONG 68W WILL ALSO INCREASE LOW-LEVEL MOISTURE CONVERGENCE AND ENHANCE ANY CONVECTION THROUGH MONDAY. ATLANTIC OCEAN... A MID-LEVEL LOW IS CENTERED OFFSHORE OF THE MID-ATLC STATES NEAR 35N74W THAT SUPPORTS AN OCCLUDED 1014 MB LOW CENTERED NEAR 34N74W. A SURFACE TROUGH EXTENDS FROM THE LOW INTO THE DISCUSSION AREA NEAR 32N75W TO 31N78W GENERATING ISOLATED SHOWERS WITHIN 75 NM EITHER SIDE OF THE BOUNDARY. FARTHER EAST...PLENTY OF MIDDLE TO UPPER LEVEL MOISTURE ADVECTION IS NOTED ON WATER VAPOR IMAGERY EAST OF THE UPPER LEVEL TROUGH AXIS EXTENDING FROM 34N73W TO THE UPPER LEVEL LOW CENTERED IN THE WESTERN CARIBBEAN SEA NEAR 17N80W. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 210 NM EITHER SIDE OF A LINE FROM 32N65W TO 20N75W FOCUSED IN THE VICINITY OF MAXIMUM LOW- LEVEL MOISTURE CONVERGENCE ALONG A SURFACE TROUGH ANALYZED FROM EASTERN CUBA NEAR 20N76W TO 29N69W. A STATIONARY FRONT EXTENDS NORTHEAST FROM THE SURFACE TROUGH TO 32N61W. ANOTHER WAVE OF LOW- LEVEL MOISTURE ROUNDING CENTRAL ATLC RIDGING IS ALIGNED ALONG AN ARC FROM 25N59W TO 19N63W TO 13N59W WITH EMBEDDED ISOLATED SHOWERS OCCURRING WITHIN 120 NM EITHER SIDE OF THE ARC. FINALLY...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1024 MB HIGH CENTERED NEAR 35N27W AND A 1024 MB HIGH CENTERED NEAR 35N13W. BRIDGING BOTH OF THESE HIGH CENTERS IS A STATIONARY FRONT\ ANALYZED FROM 33N22W TO 31N26W. ISOLATED SHOWERS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN